Temporally graded semantic memory loss in amnesia and semantic dementia: Further evidence for opposite gradients.

PubMed

Estmacott, Robyn W; Moscovitch, Morris

2002-03-01

The consolidation theory of long-term memory (e.g., Squire, 1992) predicts that damage to the medial temporal lobes will result in temporally graded retrograde memory loss, with a disproportionate impairment of recent relative to remote knowledge; in contrast, severe atrophy of the temporal neocortex is predicted to result in the reverse temporally graded pattern, with a selective sparing of recent memory (K.S. Graham & Hodges, 1997). Previously, we reported evidence that autobiographical episodic memory does not follow this temporal pattern (Westmacott, Leach, Freedman, & Moscovitch, 2001). In the present study, we found evidence suggesting that semantic memory loss does follow the predicted temporal pattern. We used a set of tasks that tap implicit and explicit memory for famous names and English vocabulary terms from across the 20th century. KC, a person with medial temporal amnesia, consistently demonstrated across tasks a selective deficit for famous names and vocabulary terms from the 5-year period just prior to injury; this deficit was particularly profound for elaborated semantic knowledge (e.g., word definitions, occupation of famous person). However, when asked to guess on unfamiliar items, KC's performance for names and words from this 5-year time period increased substantially, suggesting that he retains some of this knowledge at an implicit or rudimentary level. Conversely, EL, a semantic dementia patient with temporal neocortical atrophy and relative sparing of the medial temporal lobe, demonstrated a selective sparing of names and words from the most recent time period. However, this selective sparing of recent semantic memory was demonstrated in the implicit tasks only; performance on explicit tasks suggested an equally severe impairment of semantics across all time periods. Unlike the data from our previous study of autobiographical episodic memory, these findings are consistent with the predictions both of consolidation theory (Hodges & Graham, 1998; Squire, 1992) and multiple trace theory (Nadel & Moscovitch, 1999) that the hippocampus plays a timelimited role in the acquisition and representation of long-term semantic memories. Moreover, our findings suggest that tasks requiring minimal verbal production and explicit recall may provide a more sensitive and comprehensive assessment of intact memory capacity in brain-damaged individuals.

Cognition and the Brain

DTIC Science & Technology

1992-05-25

by a by the distinctions between short-term and long-term sensory event. As evidence they shom that %khen the ISI memory ’. episodic , semantic and...Patterson. J.V. and Starr. A. I 19S9a) ams .1 function of variations in semantic citaceori,’itions. In: D. Brain potentials in a memory scanning task. 1...number) FIELD GROUP SUB-GROUP L ocalization of cognitive processes; alpha-band suppression; memory scanning for tones; silent speech; visual image

A case of amnesia at an early age.

PubMed

Brizzolara, Daniela; Casalini, Claudia; Montanaro, Domenico; Posteraro, Federico

2003-01-01

A dissociation between short- and long-term memory (LTM) and between the episodic and the semantic component of LTM is reported in a young girl who became amnesic at the age of 6 after an episode of acute encephalopathy resulting in bilateral frontal, insular, thalamic, ponto-mesencephalic, hippocampal and temporal lesions, as documented by MRI. The girl became amnesic a few months after starting school. A follow-up investigation showed that she was able to learn to read, write and acquire number facts and procedures and to improve her semantic knowledge. Our results show that the features of adult amnesia can also be found in children and that new semantic knowledge can be acquired in spite of an anterograde memory deficit. This dissociation does not agree with theories viewing long-term declarative memory as a unitary process mediated by the hippocampal system, but supports recent hypotheses that the acquisition of semantic knowledge is independent from episodic memory processes, and takes place through spared cortical regions subjacent to the hippocampi (Vargha-Khadem et al., 1997).

Episodic and semantic memory in children with mesial temporal sclerosis.

PubMed

Rzezak, Patricia; Guimarães, Catarina; Fuentes, Daniel; Guerreiro, Marilisa M; Valente, Kette Dualibi Ramos

2011-07-01

The aim of this study was to analyze semantic and episodic memory deficits in children with mesial temporal sclerosis (MTS) and their correlation with clinical epilepsy variables. For this purpose, 19 consecutive children and adolescents with MTS (8 to 16 years old) were evaluated and their performance on five episodic memory tests (short- and long-term memory and learning) and four semantic memory tests was compared with that of 28 healthy volunteers. Patients performed worse on tests of immediate and delayed verbal episodic memory, visual episodic memory, verbal and visual learning, mental scanning for semantic clues, object naming, word definition, and repetition of sentences. Clinical variables such as early age at seizure onset, severity of epilepsy, and polytherapy impaired distinct types of memory. These data confirm that children with MTS have episodic memory deficits and add new information on semantic memory. The data also demonstrate that clinical variables contribute differently to episodic and semantic memory performance. Copyright © 2011 Elsevier Inc. All rights reserved.

Long-term memory following transient global amnesia: an investigation of episodic and semantic memory.

PubMed

Guillery-Girard, B; Quinette, P; Desgranges, B; Piolino, P; Viader, F; de la Sayette, V; Eustache, F

2006-11-01

Several studies noted persistence of memory impairment following an episode of transient global amnesia (TGA) with standard tests. To specify long-term memory impairments in a group of patients selected with stringent criteria. Both retrograde and anterograde memory were investigated in 32 patients 13-67 months after a TGA episode with original tasks encompassing retrograde semantic memory (academic, public and personal knowledge), retrograde episodic memory (autobiographical events) and anterograde episodic memory. Patients had preserved academic and public knowledge. Pathological scores were obtained in personal verbal fluency for the two most recent periods, and patients produced less autobiographical events than controls. However, when they were provided time to detail, memories were as episodic as in controls regardless of their remoteness. Anterograde episodic tasks revealed a mild but significant impairment of the capacity of re-living the condition of encoding, i.e. the moment at which words were presented. Patients who have suffered from an episode of TGA manifest deficits of memory focused on the retrieval of both recent semantic information and episodic memories and especially the capacity of re-living. These deficits may not result from a deterioration of memory per se but rather from difficulties in accessing memories.

Similarities and Differences between Working Memory and Long-Term Memory: Evidence from the Levels-of-Processing Span Task

ERIC Educational Resources Information Center

Rose, Nathan S.; Myerson, Joel; Roediger, Henry L., III; Hale, Sandra

2010-01-01

Two experiments compared the effects of depth of processing on working memory (WM) and long-term memory (LTM) using a levels-of-processing (LOP) span task, a newly developed WM span procedure that involves processing to-be-remembered words based on their visual, phonological, or semantic characteristics. Depth of processing had minimal effect on…

A Long-Term Retention Advantage for Spatial Information Learned Naturally and in the Laboratory

DTIC Science & Technology

1989-06-09

study. Memory & Cognition, 10, 324-332. Tulving, E. (1972). Episodic and semantic memory . In E. Tulving & W. Donaldson (Eds.), Organization of memory ...the cognitive research literature. Some of the better known divisions include the distinction between semantic , episodic and procedural knowledge...the probe method by being more structured and more focused on specific memory episodes . In general, questionnaire studies simply involve formulating

An Approach toward the Development of a Functional Encoding Model of Short Term Memory during Reading.

ERIC Educational Resources Information Center

Herndon, Mary Anne

1978-01-01

In a model of the functioning of short term memory, the encoding of information for subsequent storage in long term memory is simulated. In the encoding process, semantically equivalent paragraphs are detected for recombination into a macro information unit. (HOD)

Similar autobiographical memory impairment in long-term secondary progressive multiple sclerosis and Alzheimer's disease.

PubMed

Müller, S; Saur, R; Greve, B; Melms, A; Hautzinger, M; Fallgatter, A J; Leyhe, T

2013-02-01

Memory disturbance is a common symptom of multiple sclerosis (MS), but little is known about autobiographical memory deficits in the long-term course of different MS subtypes. Inflammatory activity and demyelination is pronounced in relapsing-remitting multiple sclerosis (RRMS) whereas, similar to Alzheimer's disease, neurodegeneration affecting autobiographical memory-associated areas is seen in secondary progressive multiple sclerosis (SPMS). In light of distinct disease mechanisms, we evaluated autobiographical memory in different MS subtypes and hypothesized similarities between elderly patients with SPMS and Alzheimer's disease. We used the Autobiographical Memory Interview to assess episodic and semantic autobiographical memory in 112 education- and gender-matched participants, including healthy controls and patients with RRMS, SPMS, amnesic mild cognitive impairment (aMCI) and early Alzheimer's dementia (AD). Patients with SPMS, AD, and aMCI, but not with RRMS, exhibited a pattern of episodic autobiographical memory impairment that followed Ribot's Law; older memories were better preserved than more recent memories. In contrast to aMCI and AD, neither SPMS nor RRMS was associated with semantic autobiographical memory impairment. Our neuropsychological findings suggest that episodic autobiographical memory is affected in long-term patients with SPMS, possibly due to neurodegenerative processes in functional relevant brain regions.

The effects of refreshing and elaboration on working memory performance, and their contributions to long-term memory formation.

PubMed

Bartsch, Lea M; Singmann, Henrik; Oberauer, Klaus

2018-03-19

Refreshing and elaboration are cognitive processes assumed to underlie verbal working-memory maintenance and assumed to support long-term memory formation. Whereas refreshing refers to the attentional focussing on representations, elaboration refers to linking representations in working memory into existing semantic networks. We measured the impact of instructed refreshing and elaboration on working and long-term memory separately, and investigated to what extent both processes are distinct in their contributions to working as well as long-term memory. Compared with a no-processing baseline, immediate memory was improved by repeating the items, but not by refreshing them. There was no credible effect of elaboration on working memory, except when items were repeated at the same time. Long-term memory benefited from elaboration, but not from refreshing the words. The results replicate the long-term memory benefit for elaboration, but do not support its beneficial role for working memory. Further, refreshing preserves immediate memory, but does not improve it beyond the level achieved without any processing.

Making the case that episodic recollection is attributable to operations occurring at retrieval rather than to content stored in a dedicated subsystem of long-term memory.

PubMed

Klein, Stanley B

2013-01-01

Episodic memory often is conceptualized as a uniquely human system of long-term memory that makes available knowledge accompanied by the temporal and spatial context in which that knowledge was acquired. Retrieval from episodic memory entails a form of first-person subjectivity called autonoetic consciousness that provides a sense that a recollection was something that took place in the experiencer's personal past. In this paper I expand on this definition of episodic memory. Specifically, I suggest that (1) the core features assumed unique to episodic memory are shared by semantic memory, (2) episodic memory cannot be fully understood unless one appreciates that episodic recollection requires the coordinated function of a number of distinct, yet interacting, "enabling" systems. Although these systems-ownership, self, subjective temporality, and agency-are not traditionally viewed as memorial in nature, each is necessary for episodic recollection and jointly they may be sufficient, and (3) the type of subjective awareness provided by episodic recollection (autonoetic) is relational rather than intrinsic-i.e., it can be lost in certain patient populations, thus rendering episodic memory content indistinguishable from the content of semantic long-term memory.

Long-term consolidation of declarative memory: insight from temporal lobe epilepsy.

PubMed

Tramoni, Eve; Felician, Olivier; Barbeau, Emmanuel J; Guedj, Eric; Guye, Maxime; Bartolomei, Fabrice; Ceccaldi, Mathieu

2011-03-01

Several experiments carried out with a subset of patients with temporal lobe epilepsy have demonstrated normal memory performance at standard delays of recall (i.e. minutes to hours) but impaired performance over longer delays (i.e. days or weeks), suggesting altered long-term consolidation mechanisms. These mechanisms were specifically investigated in a group of five adult-onset pharmaco-sensitive patients with temporal lobe epilepsy, exhibiting severe episodic memory complaints despite normal performance at standardized memory assessment. In a first experiment, the magnitude of autobiographical memory loss was evaluated using retrograde personal memory tasks based on verbal and visual cues. In both conditions, results showed an unusual U-shaped pattern of personal memory impairment, encompassing most of the patients' life, sparing however, periods of the childhood, early adulthood and past several weeks. This profile was suggestive of a long-term consolidation impairment of personal episodes, adequately consolidated over 'short-term' delays but gradually forgotten thereafter. Therefore, in a subsequent experiment, patients were submitted to a protocol specifically devised to investigate short and long-term consolidation of contextually-bound experiences (episodic memory) and context-free information (semantic knowledge and single-items). In the short term (1 h), performance at both contextually-free and contextually-bound memory tasks was intact. After a 6-week delay, however, contextually-bound memory performance was impaired while contextually-free memory performance remained preserved. This effect was independent of task difficulty and the modality of retrieval (recall and recognition). Neuroimaging studies revealed the presence of mild metabolic changes within medial temporal lobe structures. Taken together, these results show the existence of different consolidation systems within declarative memory. They suggest that mild medial temporal lobe dysfunction can impede the building and stabilization of episodic memories but leaves long-term semantic and single-items mnemonic traces intact.

When music and long-term memory interact: effects of musical expertise on functional and structural plasticity in the hippocampus.

PubMed

Groussard, Mathilde; La Joie, Renaud; Rauchs, Géraldine; Landeau, Brigitte; Chételat, Gaël; Viader, Fausto; Desgranges, Béatrice; Eustache, Francis; Platel, Hervé

2010-10-05

The development of musical skills by musicians results in specific structural and functional modifications in the brain. Surprisingly, no functional magnetic resonance imaging (fMRI) study has investigated the impact of musical training on brain function during long-term memory retrieval, a faculty particularly important in music. Thus, using fMRI, we examined for the first time this process during a musical familiarity task (i.e., semantic memory for music). Musical expertise induced supplementary activations in the hippocampus, medial frontal gyrus, and superior temporal areas on both sides, suggesting a constant interaction between episodic and semantic memory during this task in musicians. In addition, a voxel-based morphometry (VBM) investigation was performed within these areas and revealed that gray matter density of the hippocampus was higher in musicians than in nonmusicians. Our data indicate that musical expertise critically modifies long-term memory processes and induces structural and functional plasticity in the hippocampus.

Association of KIBRA and memory.

PubMed

Bates, Timothy C; Price, Jackie F; Harris, Sarah E; Marioni, Riccardo E; Fowkes, F Gerry R; Stewart, Marlene C; Murray, Gordon D; Whalley, Lawrence J; Starr, John M; Deary, Ian J

2009-07-24

We report on the association of KIBRA with memory in two samples of older individuals assessed on either memory for semantically unrelated word stimuli (Rey Auditory Verbal Learning Test, n=2091), or a measure of semantically related material (the WAIS Logical Memory Test of prose-passage recall, n=542). SNP rs17070145 was associated with delayed recall of semantically unrelated items, but not with immediate recall for these stimuli, nor with either immediate or delayed recall for semantically related material. The pattern of results suggests a role for the T-->C substitution in intron 9 of KIBRA in a component of episodic memory involved in long-term storage but independent of processes shared with immediate recall such as rehearsal involved in acquisition and rehearsal or processes.

NEREC, an effective brain mapping protocol for combined language and long-term memory functions.

PubMed

Perrone-Bertolotti, Marcela; Girard, Cléa; Cousin, Emilie; Vidal, Juan Ricardo; Pichat, Cédric; Kahane, Philippe; Baciu, Monica

2015-12-01

Temporal lobe epilepsy can induce functional plasticity in temporoparietal networks involved in language and long-term memory processing. Previous studies in healthy subjects have revealed the relative difficulty for this network to respond effectively across different experimental designs, as compared to more reactive regions such as frontal lobes. For a protocol to be optimal for clinical use, it has to first show robust effects in a healthy cohort. In this study, we developed a novel experimental paradigm entitled NEREC, which is able to reveal the robust participation of temporoparietal networks in a uniquely combined language and memory task, validated in an fMRI study with healthy subjects. Concretely, NEREC is composed of two runs: (a) an intermixed language-memory task (confrontation naming associated with encoding in nonverbal items, NE) to map language (i.e., word retrieval and lexico-semantic processes) combined with simultaneous long-term verbal memory encoding (NE items named but also explicitly memorized) and (b) a memory retrieval task of items encoded during NE (word recognition, REC) intermixed with new items. Word recognition is based on both perceptual-semantic familiarity (feeling of 'know') and accessing stored memory representations (remembering). In order to maximize the remembering and recruitment of medial temporal lobe structures, we increased REC difficulty by changing the modality of stimulus presentation (from nonverbal during NE to verbal during REC). We report that (a) temporoparietal activation during NE was attributable to both lexico-semantic (language) and memory (episodic encoding and semantic retrieval) processes; that (b) encoding activated the left hippocampus, bilateral fusiform, and bilateral inferior temporal gyri; and that (c) task recognition (recollection) activated the right hippocampus and bilateral but predominant left fusiform gyrus. The novelty of this protocol consists of (a) combining two tasks in one (language and long-term memory encoding/recall) instead of applying isolated tasks to map temporoparietal regions, (b) analyzing NE data based on performances recorded during REC, (c) double-mapping networks involved in naming and in long-term memory encoding and retrieval, (d) focusing on remembering with hippocampal activation and familiarity judgment with lateral temporal cortices activation, and (e) short duration of examination and feasibility. These aspects are of particular interest in patients with TLE, who frequently show impairment of these cognitive functions. Here, we show that the novel protocol is suited for this clinical evaluation. Copyright © 2015 Elsevier Inc. All rights reserved.

False Memories Seconds Later: The Rapid and Compelling Onset of Illusory Recognition

ERIC Educational Resources Information Center

Flegal, Kristin E.; Atkins, Alexandra S.; Reuter-Lorenz, Patricia A.

2010-01-01

Distortions of long-term memory (LTM) in the converging associates task are thought to arise from semantic associative processes and monitoring failures due to degraded verbatim and/or contextual memory. Sensory-based coding is traditionally considered more prevalent than meaning-based coding in short-term memory (STM), whereas the converse is…

Hearing loss is negatively related to episodic and semantic long-term memory but not to short-term memory.

PubMed

Rönnberg, Jerker; Danielsson, Henrik; Rudner, Mary; Arlinger, Stig; Sternäng, Ola; Wahlin, Ake; Nilsson, Lars-Göran

2011-04-01

To test the relationship between degree of hearing loss and different memory systems in hearing aid users. Structural equation modeling (SEM) was used to study the relationship between auditory and visual acuity and different cognitive and memory functions in an age-hetereogenous subsample of 160 hearing aid users without dementia, drawn from the Swedish prospective cohort aging study known as Betula (L.-G. Nilsson et al., 1997). Hearing loss was selectively and negatively related to episodic and semantic long-term memory (LTM) but not short-term memory (STM) performance. This held true for both ears, even when age was accounted for. Visual acuity alone, or in combination with auditory acuity, did not contribute to any acceptable SEM solution. The overall relationships between hearing loss and memory systems were predicted by the ease of language understanding model (J. Rönnberg, 2003), but the exact mechanisms of episodic memory decline in hearing aid users (i.e., mismatch/disuse, attentional resources, or information degradation) remain open for further experiments. The hearing aid industry should strive to design signal processing algorithms that are cognition friendly.

Aging and Semantic Activation.

ERIC Educational Resources Information Center

Howard, Darlene V.

Three studies tested the theory that long term memory consists of a semantically organized network of concept nodes interconnected by leveled associations or relations, and that when a stimulus is processed, the corresponding concept node is assumed to be temporarily activated and this activation spreads to nearby semantically related nodes. In…

Self-referential processing is distinct from semantic elaboration: evidence from long-term memory effects in a patient with amnesia and semantic impairments.

PubMed

Sui, Jie; Humphreys, Glyn W

2013-11-01

We report data demonstrating that self-referential encoding facilitates memory performance in the absence of effects of semantic elaboration in a severely amnesic patient also suffering semantic problems. In Part 1, the patient, GA, was trained to associate items with the self or a familiar other during the encoding phase of a memory task (self-ownership decisions in Experiment 1 and self-evaluation decisions in Experiment 2). Tests of memory showed a consistent self-reference advantage, relative to a condition where the reference was another person in both experiments. The pattern of the self-reference advantage was similar to that in healthy controls. In Part 2 we demonstrate that GA showed minimal effects of semantic elaboration on memory for items he semantically classified, compared with items subject to physical size decisions; in contrast, healthy controls demonstrated enhanced memory performance after semantic relative to physical encoding. The results indicate that self-referential encoding, not semantic elaboration, improves memory in amnesia. Self-referential processing may provide a unique scaffold to help improve learning in amnesic cases. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Role of Semantic Features in Verb Processing

ERIC Educational Resources Information Center

Bonnotte, Isabelle

2008-01-01

The present study examined the general hypothesis that, as for nouns, stable representations of semantic knowledge relative to situations expressed by verbs are available and accessible in long term memory in normal people. Regular associations between verbs and past tenses in French adults allowed to abstract two superordinate semantic features…

Strategic search from long-term memory: an examination of semantic and autobiographical recall.

PubMed

Unsworth, Nash; Brewer, Gene A; Spillers, Gregory J

2014-01-01

Searching long-term memory is theoretically driven by both directed (search strategies) and random components. In the current study we conducted four experiments evaluating strategic search in semantic and autobiographical memory. Participants were required to generate either exemplars from the category of animals or the names of their friends for several minutes. Self-reported strategies suggested that participants typically relied on visualization strategies for both tasks and were less likely to rely on ordered strategies (e.g., alphabetic search). When participants were instructed to use particular strategies, the visualization strategy resulted in the highest levels of performance and the most efficient search, whereas ordered strategies resulted in the lowest levels of performance and fairly inefficient search. These results are consistent with the notion that retrieval from long-term memory is driven, in part, by search strategies employed by the individual, and that one particularly efficient strategy is to visualize various situational contexts that one has experienced in the past in order to constrain the search and generate the desired information.

Making the case that episodic recollection is attributable to operations occurring at retrieval rather than to content stored in a dedicated subsystem of long-term memory

PubMed Central

Klein, Stanley B.

2013-01-01

Episodic memory often is conceptualized as a uniquely human system of long-term memory that makes available knowledge accompanied by the temporal and spatial context in which that knowledge was acquired. Retrieval from episodic memory entails a form of first–person subjectivity called autonoetic consciousness that provides a sense that a recollection was something that took place in the experiencer's personal past. In this paper I expand on this definition of episodic memory. Specifically, I suggest that (1) the core features assumed unique to episodic memory are shared by semantic memory, (2) episodic memory cannot be fully understood unless one appreciates that episodic recollection requires the coordinated function of a number of distinct, yet interacting, “enabling” systems. Although these systems—ownership, self, subjective temporality, and agency—are not traditionally viewed as memorial in nature, each is necessary for episodic recollection and jointly they may be sufficient, and (3) the type of subjective awareness provided by episodic recollection (autonoetic) is relational rather than intrinsic—i.e., it can be lost in certain patient populations, thus rendering episodic memory content indistinguishable from the content of semantic long-term memory. PMID:23378832

Similarities and Differences Between Working Memory and Long-Term Memory: Evidence From the Levels-of-Processing Span Task

PubMed Central

Rose, Nathan S.; Myerson, Joel; Roediger, Henry L.; Hale, Sandra

2010-01-01

Two experiments compared the effects of depth of processing on working memory (WM) and long-term memory (LTM) using a levels-of-processing (LOP) span task, a newly developed WM span procedure that involves processing to-be-remembered words based on their visual, phonological, or semantic characteristics. Depth of processing had minimal effect on WM tests, yet subsequent memory for the same items on delayed tests showed the typical benefits of semantic processing. Although the difference in LOP effects demonstrates a dissociation between WM and LTM, we also found that the retrieval practice provided by recalling words on the WM task benefited long-term retention, especially for words initially recalled from supraspan lists. The latter result is consistent with the hypothesis that WM span tasks involve retrieval from secondary memory, but the LOP dissociation suggests the processes engaged by WM and LTM tests may differ. Therefore, similarities and differences between WM and LTM depend on the extent to which retrieval from secondary memory is involved and whether there is a match (or mismatch) between initial processing and subsequent retrieval, consistent with transfer-appropriate-processing theory. PMID:20192543

Hearing Loss Is Negatively Related to Episodic and Semantic Long-Term Memory but Not to Short-Term Memory

ERIC Educational Resources Information Center

Ronnberg, Jerker; Danielsson, Henrik; Rudner, Mary; Arlinger, Stig; Sternang, Ola; Wahlin, Ake; Nilsson, Lars-Goran

2011-01-01

Purpose: To test the relationship between degree of hearing loss and different memory systems in hearing aid users. Method: Structural equation modeling (SEM) was used to study the relationship between auditory and visual acuity and different cognitive and memory functions in an age-hetereogenous subsample of 160 hearing aid users without…

Two retrievals from a single cue: A bottleneck persists across episodic and semantic memory.

PubMed

Orscheschek, Franziska; Strobach, Tilo; Schubert, Torsten; Rickard, Timothy

2018-05-01

There is evidence in the literature that two retrievals from long-term memory cannot occur in parallel. To date, however, that work has explored only the case of two retrievals from newly acquired episodic memory. These studies demonstrated a retrieval bottleneck even after dual-retrieval practice. That retrieval bottleneck may be a global property of long-term memory retrieval, or it may apply only to the case of two retrievals from episodic memory. In the current experiments, we explored whether that apparent dual-retrieval bottleneck applies to the case of one retrieval from episodic memory and one retrieval from highly overlearned semantic memory. Across three experiments, subjects learned to retrieve a left or right keypress response form a set of 14 unique word cues (e.g., black-right keypress). In addition, they learned a verbal response which involved retrieving the antonym of the presented cue (e.g., black-"white"). In the dual-retrieval condition, subjects had to retrieve both the keypress response and the antonym word. The results suggest that the retrieval bottleneck is superordinate to specific long-term memory systems and holds across different memory components. In addition, the results support the assumption of a cue-level response chunking account of learned retrieval parallelism.

Event-related rTMS at encoding affects differently deep and shallow memory traces.

PubMed

Innocenti, Iglis; Giovannelli, Fabio; Cincotta, Massimo; Feurra, Matteo; Polizzotto, Nicola R; Bianco, Giovanni; Cappa, Stefano F; Rossi, Simone

2010-10-15

The "level of processing" effect is a classical finding of the experimental psychology of memory. Actually, the depth of information processing at encoding predicts the accuracy of the subsequent episodic memory performance. When the incoming stimuli are analyzed in terms of their meaning (semantic, or deep, encoding), the memory performance is superior with respect to the case in which the same stimuli are analyzed in terms of their perceptual features (shallow encoding). As suggested by previous neuroimaging studies and by some preliminary findings with transcranial magnetic stimulation (TMS), the left prefrontal cortex may play a role in semantic processing requiring the allocation of working memory resources. However, it still remains unclear whether deep and shallow encoding share or not the same cortical networks, as well as how these networks contribute to the "level of processing" effect. To investigate the brain areas casually involved in this phenomenon, we applied event-related repetitive TMS (rTMS) during deep (semantic) and shallow (perceptual) encoding of words. Retrieval was subsequently tested without rTMS interference. RTMS applied to the left dorsolateral prefrontal cortex (DLPFC) abolished the beneficial effect of deep encoding on memory performance, both in terms of accuracy (decrease) and reaction times (increase). Neither accuracy nor reaction times were instead affected by rTMS to the right DLPFC or to an additional control site excluded by the memory process (vertex). The fact that online measures of semantic processing at encoding were unaffected suggests that the detrimental effect on memory performance for semantically encoded items took place in the subsequent consolidation phase. These results highlight the specific causal role of the left DLPFC among the wide left-lateralized cortical network engaged by long-term memory, suggesting that it probably represents a crucial node responsible for the improved memory performance induced by semantic processing. Copyright 2010 Elsevier Inc. All rights reserved.

Human hippocampus associates information in memory

PubMed Central

Henke, Katharina; Weber, Bruno; Kneifel, Stefan; Wieser, Heinz Gregor; Buck, Alfred

1999-01-01

The hippocampal formation, one of the most complex and vulnerable brain structures, is recognized as a crucial brain area subserving human long-term memory. Yet, its specific functions in memory are controversial. Recent experimental results suggest that the hippocampal contribution to human memory is limited to episodic memory, novelty detection, semantic (deep) processing of information, and spatial memory. We measured the regional cerebral blood flow by positron-emission tomography while healthy volunteers learned pairs of words with different learning strategies. These led to different forms of learning, allowing us to test the degree to which they challenge hippocampal function. Neither novelty detection nor depth of processing activated the hippocampal formation as much as semantically associating the primarily unrelated words in memory. This is compelling evidence for another function of the human hippocampal formation in memory: establishing semantic associations. PMID:10318979

Acquired amnesia in childhood: a single case study.

PubMed

Vicari, Stefano; Menghini, Deny; Di Paola, Margherita; Serra, Laura; Donfrancesco, Alberto; Fidani, Paola; Milano, Giuseppe Maria; Carlesimo, Giovanni Augusto

2007-03-02

We report the case of C.L., an 8-year-old child who, following the surgical removal of an ependymoma from the left cerebral ventricle at the age of 4 years, developed significant difficulties in retaining day-to-day events and information. A thorough neuropsychological analysis documented in C.L. a severe anterograde amnesic syndrome, characterised by normal short-term memory, but poor performance on episodic long-term memory tests. In particular, C.L. demonstrated virtually no ability to recollect new verbal information several minutes after the presentation. As for semantic memory, C.L. demonstrated general semantic competencies, which, depending on the test, ranged from the level of a 6-year-old girl to a level corresponding to her actual chronological age. Finding a patient who, despite being severely impaired in the ability to recollect new episodic memories, still demonstrates at least partially preserved abilities to acquire new semantic knowledge suggests that neural circuits implicated in the memorisation of autobiographical events and factual information do not overlap completely. This case is examined in the light of growing literature concerned with the dissociation between episodic and semantic memory in childhood amnesia.

Attention, Imagery and Memory: A Neuromagnetic Investigation

DTIC Science & Technology

1991-10-14

The full complexity of memory processes suggested by the distinctions between short-term and long-term memory , episodic , semantic and declarative...the ;canning of short-term memory . This fol- lows from the fact that bilateral damage to medial temporal cortex results in anterograde amnesia , which...Neural Science AD-A243 859 r󈧅 FINAL TECHNICAL REPORTC Attention, Imagery and Memory 1 March 1988 -30 September 1991 , Q6’i iQ’ UA Dr.~~~~C A..Fel

The N400 reveals how personal semantics is processed: Insights into the nature and organization of self-knowledge

PubMed Central

Federmeier, Kara D.

2017-01-01

There is growing recognition that some important forms of long-term memory are difficult to classify into one of the well-studied memory subtypes. One example is personal semantics. Like the episodes that are stored as part of one’s autobiography, personal semantics is linked to an individual, yet, like general semantic memory, it is detached from a specific encoding context. Access to general semantics elicits an electrophysiological response known as the N400, which has been characterized across three decades of research; surprisingly, this response has not been fully examined in the context of personal semantics. In this study, we assessed responses to congruent and incongruent statements about people’s own, personal preferences. We found that access to personal preferences elicited N400 responses, with congruency effects that were similar in latency and distribution to those for general semantic statements elicited from the same participants. These results suggest that the processing of personal and general semantics share important functional and neurobiological features. PMID:26825011

Developmental roots of episodic memory.

PubMed

Nelson, Katherine

2018-01-01

Two arguments imply that Mahr & Csibra's (M&C's) functional theory is insufficient as an explanation of episodic memory: (1) The developmental course supports a different social cultural division of episodic and semantic memory, and (2) the existence of long-term autobiographical memory is not explained in the functional theory but can be seen in a broader cultural framework.

A critical evaluation of monkey models of amnesia and dementia.

PubMed

Ridley, R M; Baker, H F

1991-01-01

In this review we consider various models of amnesia and dementia in monkeys and examine the validity of such models. In Section 2 we describe the various types of memory tests (tasks) available for use with monkeys and discuss the extent to which these tasks assess different facets of memory according to present theories of human memory. We argue that the rules which govern correct task performance are best regarded as a form of semantic rather than procedural memory, and that when information about stimulus attributes or reward associations is stored long-term then that knowledge is semantic. The demonstration of episodic memory in monkeys is problematic and the term recognition memory has been used too loosely. In particular, it is difficult to dissociate episodic memory for stimulus events from the use of semantic memory for the rule of the task, since dysfunction of either can produce impairment on performance of the same task. Tasks can also be divided into those which assess memory for stimulus-reward associations (evaluative memory) and those which tax stimulus-response associations including spatial and conditional responding (non-evaluative memory). This dissociation cuts across the distinction between semantic and episodic memory. In Section 3 we examine the usefulness of the classification of tasks described in Section 2 in clarifying our understanding of the contribution of the temporal lobes and the cholinergic system to memory. We conclude that evaluative and non-evaluative memory are mediated by separate parallel systems involving the amygdala and hippocampus, respectively.

A familiar pattern? Semantic memory contributes to the enhancement of visuo-spatial memories.

PubMed

Riby, Leigh M; Orme, Elizabeth

2013-03-01

In this study we quantify for the first time electrophysiological components associated with incorporating long-term semantic knowledge with visuo-spatial information using two variants of a traditional matrix patterns task. Results indicated that the matrix task with greater semantic content was associated with enhanced accuracy and RTs in a change-detection paradigm; this was also associated with increased P300 and N400 components as well as a sustained negative slow wave (NSW). In contrast, processing of the low semantic stimuli was associated with an increased N200 and a reduction in the P300. These findings suggest that semantic content can aid in reducing early visual processing of information and subsequent memory load by unitizing complex patterns into familiar forms. The N400/NSW may be associated with the requirements for maintaining visuo-spatial information about semantic forms such as orientation and relative location. Evidence for individual differences in semantic elaboration strategies used by participants is also discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

Event-related brain potentials that distinguish false memory for events that occurred only seconds in the past.

PubMed

Chen, Hong; Voss, Joel L; Guo, Chunyan

2012-07-30

False memory often involves retrieving events from the distant past that did not actually happen. However, recent evidence obtained using the Deese/Roediger-McDermott (DRM) paradigm for eliciting false memory experiences suggests that individuals can falsely believe that events occurred mere seconds in the past when they in fact did not. Subjects in these experiments endorsed unstudied critical lure words as having been studied, despite the fact that word lists were studied just moments before. We identified event-related brain potential (ERP) correlates of this experience, and included a repetition priming manipulation to better assess the functional significance of these ERPs. Behavioral and ERP data were collected from 21 Capital Normal University students using a short-term DRM task. Two categories of effects were identified that distinguished true from false short-term memory: (1) early semantic priming effects from 300 to 500 ms and (2) later retrieval and retrieval-monitoring effects after 500 ms. The repetition priming manipulation had distinct influences on these effects, consistent with their differential associations with semantic priming versus episodic retrieval. Characterization of ERPs related to semantic priming and episodic retrieval provides important information regarding the mechanisms of short-term false memory. In contrast, most studies examining false memory in standard long-delay DRM paradigms identify ERP effects related only to retrieval monitoring. These findings highlight the neural processing involved in illusions of memory after very brief delays and highlight the role of semantic processing in short-term false memory.

Event-related brain potentials that distinguish false memory for events that occurred only seconds in the past

PubMed Central

2012-01-01

Background False memory often involves retrieving events from the distant past that did not actually happen. However, recent evidence obtained using the Deese/Roediger-McDermott (DRM) paradigm for eliciting false memory experiences suggests that individuals can falsely believe that events occurred mere seconds in the past when they in fact did not. Subjects in these experiments endorsed unstudied critical lure words as having been studied, despite the fact that word lists were studied just moments before. We identified event-related brain potential (ERP) correlates of this experience, and included a repetition priming manipulation to better assess the functional significance of these ERPs. Methods Behavioral and ERP data were collected from 21 Capital Normal University students using a short-term DRM task. Results Two categories of effects were identified that distinguished true from false short-term memory: (1) early semantic priming effects from 300 to 500 ms and (2) later retrieval and retrieval-monitoring effects after 500 ms. The repetition priming manipulation had distinct influences on these effects, consistent with their differential associations with semantic priming versus episodic retrieval. Conclusion Characterization of ERPs related to semantic priming and episodic retrieval provides important information regarding the mechanisms of short-term false memory. In contrast, most studies examining false memory in standard long-delay DRM paradigms identify ERP effects related only to retrieval monitoring. These findings highlight the neural processing involved in illusions of memory after very brief delays and highlight the role of semantic processing in short-term false memory. PMID:22846189

Dynamic switching between semantic and episodic memory systems.

PubMed

Kompus, Kristiina; Olsson, Carl-Johan; Larsson, Anne; Nyberg, Lars

2009-09-01

It has been suggested that episodic and semantic long-term memory systems interact during retrieval. Here we examined the flexibility of memory retrieval in an associative task taxing memories of different strength, assumed to differentially engage episodic and semantic memory. Healthy volunteers were pre-trained on a set of 36 face-name pairs over a 6-week period. Another set of 36 items was shown only once during the same time period. About 3 months after the training period all items were presented in a randomly intermixed order in an event-related fMRI study of face-name memory. Once presented items differentially activated anterior cingulate cortex and a right prefrontal region that previously have been associated with episodic retrieval mode. High-familiar items were associated with stronger activation of posterior cortices and a left frontal region. These findings fit a model of memory retrieval by which early processes determine, on a trial-by-trial basis, if the task can be solved by the default semantic system. If not, there is a dynamic shift to cognitive control processes that guide retrieval from episodic memory.

Preserved semantic access in global amnesia and hippocampal damage.

PubMed

Giovagnoli, A R; Erbetta, A; Bugiani, O

2001-12-01

C.B., a right-handed 33-year-old man, presented with anterograde amnesia after acute heart block. Cognitive abilities were normal except for serious impairment of long-term episodic memory. The access to semantic information was fully preserved. Magnetic resonance showed high signal intensity and marked volume loss in the hippocampus bilaterally; the left and right parahippocampal gyrus, lateral occipito-temporal gyrus, inferior temporal gyrus, and lateral temporal cortex were normal. This case underlines that global amnesia associated with hippocampal damage does not affect semantic memory. Although the hippocampus is important in retrieving context-linked information, its role is not so crucial in retrieving semantic contents. Cortical areas surrounding the hippocampus and lateral temporal areas might guide the recall of semantic information.

Neuroplastic Response After Radiation Therapy for Pediatric Brain Tumors: A Pilot Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armstrong, Carol L., E-mail: armstrongc@email.chop.edu; Fisher, Michael J.; Li, Yimei

Purpose: Clinically effective measurement of cognitive toxicity from photon radiation therapy (XRT) should be accurate, sensitive, and specific. This pilot study tested translational findings on phasic changes in children's memory systems that are sensitive and insensitive to toxic XRT effects to identify a possible neuroplastic effect. Methods and Materials: Memory processes were prospectively tested before XRT and at 3 later time points up to 2 years in 35 children with mixed primary brain tumors who had not experienced recurrence. Memory processes were verbal-semantic, visual-semantic, and visual-perceptual, including accuracy, speed to recall, encoding, retrieval, and recognition. The mixed-effects model included time (tomore » estimate slope), covariates (age, tumor locus, XRT field, and medications) as fixed effects, and individual random intercepts. A sensitivity analysis examined the influence of XRT dose to the hippocampi on memory. Results: Retrieval from long-term verbal-semantic memory declined 2 months after completing XRT, as seen in adults, and was lowest at 1 year, which was delayed in comparison with adults. Double dissociation from visual-perceptual memory at baseline and 2 months was found, consistent with adults. Recovery was demonstrated 2 years after XRT. Patterns were unchanged when dose to hippocampus was included in the model. Conclusions: Verbal and semantic long-term retrieval is specifically sensitive to XRT-related cognitive dysfunction, without effect on visual-perceptual memory. Children reached nadir in XRT-sensitive memory 1 year after XRT and recovered by 2 years, which is later than that observed in adults. The protracted period of post-XRT injury may represent the maturation of the human hippocampus and white matter into late adolescence.« less

Get the gist? The effects of processing depth on false recognition in short-term and long-term memory.

PubMed

Flegal, Kristin E; Reuter-Lorenz, Patricia A

2014-07-01

Gist-based processing has been proposed to account for robust false memories in the converging-associates task. The deep-encoding processes known to enhance verbatim memory also strengthen gist memory and increase distortions of long-term memory (LTM). Recent research has demonstrated that compelling false memory illusions are relatively delay-invariant, also occurring under canonical short-term memory (STM) conditions. To investigate the contributions of gist to false memory at short and long delays, processing depth was manipulated as participants encoded lists of four semantically related words and were probed immediately, following a filled 3- to 4-s retention interval, or approximately 20 min later, in a surprise recognition test. In two experiments, the encoding manipulation dissociated STM and LTM on the frequency, but not the phenomenology, of false memory. Deep encoding at STM increases false recognition rates at LTM, but confidence ratings and remember/know judgments are similar across delays and do not differ as a function of processing depth. These results suggest that some shared and some unique processes underlie false memory illusions at short and long delays.

Phonology without semantics? Good enough for verbal short-term memory. Evidence from a patient with semantic dementia.

PubMed

Papagno, Costanza; Vernice, Mirta; Cecchetto, Carlo

2013-03-01

There is considerable evidence that long-term knowledge has an influence on short-term memory (STM) performance. This reflects the activation of long-term representations involved in perceiving and comprehending spoken language. Still, this type of long-term knowledge might be of two different kinds. STM performance might be facilitated by information about the meaning of the word, or, alternatively, by familiarity with its phonological form. We investigated these two alternatives by assessing word span in MC, a patient with semantic dementia. Four different lists of words were used: known words, words whose phonological form was known by the patient although she could not report its meaning, words that the patient did not recognize as words and judged as nonwords, nonwords. The patient's performance was compared to that of six matched controls. MC did not differ from controls in the first two types of lists and performed at the same level with both, while for words whose phonological form was unknown (and therefore not recognized as words) her performance was comparable to that with nonwords; also, with this type of item, she produced significantly more phonemic substitutions than controls. The results show that long-term knowledge facilitates immediate serial recall. However, this facilitation is due to familiarity with phonological representations rather than to knowledge of meaning. Copyright © 2012 Elsevier Ltd. All rights reserved.

Visuospatial working memory in children with autism: the effect of a semantic global organization.

PubMed

Mammarella, Irene C; Giofrè, David; Caviola, Sara; Cornoldi, Cesare; Hamilton, Colin

2014-06-01

It has been reported that individuals with Autism Spectrum Disorders (ASD) perceive visual scenes as a sparse set of details rather than as a congruent and meaningful unit, failing in the extraction of the global configuration of the scene. In the present study, children with ASD were compared with typically developing (TD) children, in a visuospatial working memory task, the Visual Patterns Test (VPT). The VPT array was manipulated to vary the semantic affordance of the pattern, high semantic (global) vs. low semantic; temporal parameters were also manipulated within the change detection protocol. Overall, there was no main effect associated with Group, however there was a significant effect associated with Semantics, which was further qualified by an interaction between the Group and Semantic factors; there was only a significant effect of semantics in the TD group. The findings are discussed in light of the weak central coherence theory where the ASD group are unable to make use of long term memory semantics in order to construct global representations of the array. Copyright © 2014 Elsevier Ltd. All rights reserved.

The N400 reveals how personal semantics is processed: Insights into the nature and organization of self-knowledge.

PubMed

Coronel, Jason C; Federmeier, Kara D

2016-04-01

There is growing recognition that some important forms of long-term memory are difficult to classify into one of the well-studied memory subtypes. One example is personal semantics. Like the episodes that are stored as part of one's autobiography, personal semantics is linked to an individual, yet, like general semantic memory, it is detached from a specific encoding context. Access to general semantics elicits an electrophysiological response known as the N400, which has been characterized across three decades of research; surprisingly, this response has not been fully examined in the context of personal semantics. In this study, we assessed responses to congruent and incongruent statements about people's own, personal preferences. We found that access to personal preferences elicited N400 responses, with congruency effects that were similar in latency and distribution to those for general semantic statements elicited from the same participants. These results suggest that the processing of personal and general semantics share important functional and neurobiological features. Copyright © 2016 Elsevier Ltd. All rights reserved.

Selective Short-Term Memory Deficits Arise from Impaired Domain-General Semantic Control Mechanisms

ERIC Educational Resources Information Center

Hoffman, Paul; Jefferies, Elizabeth; Ehsan, Sheeba; Hopper, Samantha; Lambon Ralph, Matthew A.

2009-01-01

Semantic short-term memory (STM) patients have a reduced ability to retain semantic information over brief delays but perform well on other semantic tasks; this pattern suggests damage to a dedicated buffer for semantic information. Alternatively, these difficulties may arise from mild disruption to domain-general semantic processes that have…

Presentation format effects in a levels-of-processing task.

PubMed

Foos, Paul W; Goolkasian, Paula

2008-01-01

Three experiments were conducted to examine better performance in long-term memory when stimulus items are pictures or spoken words compared to printed words. Hypotheses regarding the allocation of attention to printed words, the semantic link between pictures and processing, and a rich long-term representation for pictures were tested. Using levels-of-processing tasks eliminated format effects when no memory test was expected and processing was deep (El), and when study and test formats did not match (E3). Pictures produced superior performance when a memory test was expected (El & 2) and when study and test formats were the same (E3). Results of all experiments support the attenuation of attention model and that picture superiority is due to a more direct access to semantic processing and a richer visual code. General principles to guide the processing of stimulus information are discussed.

Semantic and Visual Memory After Alcohol Abuse.

ERIC Educational Resources Information Center

Donat, Dennis C.

1986-01-01

Compared the relative performance of 40 patients with a history of alcohol abuse on tasks of short-term semantic and visual memory. Performance on the visual memory tasks was impaired significantly relative to the semantic memory task in a within-subjects analysis of variance. Semantic memory was unimpaired. (Author/ABB)

Keeping it together: Semantic coherence stabilizes phonological sequences in short-term memory.

PubMed

Savill, Nicola; Ellis, Rachel; Brooke, Emma; Koa, Tiffany; Ferguson, Suzie; Rojas-Rodriguez, Elena; Arnold, Dominic; Smallwood, Jonathan; Jefferies, Elizabeth

2018-04-01

Our ability to hold a sequence of speech sounds in mind, in the correct configuration, supports many aspects of communication, but the contribution of conceptual information to this basic phonological capacity remains controversial. Previous research has shown modest and inconsistent benefits of meaning on phonological stability in short-term memory, but these studies were based on sets of unrelated words. Using a novel design, we examined the immediate recall of sentence-like sequences with coherent meaning, alongside both standard word lists and mixed lists containing words and nonwords. We found, and replicated, substantial effects of coherent meaning on phoneme-level accuracy: The phonemes of both words and nonwords within conceptually coherent sequences were more likely to be produced together and in the correct order. Since nonwords do not exist as items in long-term memory, the semantic enhancement of phoneme-level recall for both item types cannot be explained by a lexically based item reconstruction process employed at the point of retrieval ("redintegration"). Instead, our data show, for naturalistic input, that when meaning emerges from the combination of words, the phonological traces that support language are reinforced by a semantic-binding process that has been largely overlooked by past short-term memory research.

Semantic Congruence Accelerates the Onset of the Neural Signals of Successful Memory Encoding.

PubMed

Packard, Pau A; Rodríguez-Fornells, Antoni; Bunzeck, Nico; Nicolás, Berta; de Diego-Balaguer, Ruth; Fuentemilla, Lluís

2017-01-11

As the stream of experience unfolds, our memory system rapidly transforms current inputs into long-lasting meaningful memories. A putative neural mechanism that strongly influences how input elements are transformed into meaningful memory codes relies on the ability to integrate them with existing structures of knowledge or schemas. However, it is not yet clear whether schema-related integration neural mechanisms occur during online encoding. In the current investigation, we examined the encoding-dependent nature of this phenomenon in humans. We showed that actively integrating words with congruent semantic information provided by a category cue enhances memory for words and increases false recall. The memory effect of such active integration with congruent information was robust, even with an interference task occurring right after each encoding word list. In addition, via electroencephalography, we show in 2 separate studies that the onset of the neural signals of successful encoding appeared early (∼400 ms) during the encoding of congruent words. That the neural signals of successful encoding of congruent and incongruent information followed similarly ∼200 ms later suggests that this earlier neural response contributed to memory formation. We propose that the encoding of events that are congruent with readily available contextual semantics can trigger an accelerated onset of the neural mechanisms, supporting the integration of semantic information with the event input. This faster onset would result in a long-lasting and meaningful memory trace for the event but, at the same time, make it difficult to distinguish it from plausible but never encoded events (i.e., related false memories). Conceptual or schema congruence has a strong influence on long-term memory. However, the question of whether schema-related integration neural mechanisms occur during online encoding has yet to be clarified. We investigated the neural mechanisms reflecting how the active integration of words with congruent semantic categories enhances memory for words and increases false recall of semantically related words. We analyzed event-related potentials during encoding and showed that the onset of the neural signals of successful encoding appeared early (∼400 ms) during the encoding of congruent words. Our findings indicate that congruent events can trigger an accelerated onset of neural encoding mechanisms supporting the integration of semantic information with the event input. Copyright © 2017 the authors 0270-6474/17/370291-11$15.00/0.

The role of semantic memory in short-term recall: effect of strategic retrieval ability in an elderly population.

PubMed

Larigauderie, Pascale; Michaud, Aurelie; Vicente, Siobhan

2011-03-01

The present paper examines the relationship between two classic phenomena: semantic effects in short-term recall (STR) tasks, which are interpreted as indicating the involvement of long-term memory (LTM) in the functioning of short-term memory, on the one hand, and the existence of individual differences amongst elderly people in strategic retrieval ability (i.e., the ability to activate representations in LTM in a controlled way) on the other hand. Forty elderly participants completed a STR task under four different conditions which were thought to differentially involve LTM representations. Several executive functions, among which the strategic retrieval ability, were evaluated. The results showed that the participants who obtained the best performances in terms of strategic retrieval ability, and only in this executive ability, also exhibited better performances in the STR task, in particular when this task was performed under conditions which favored the use of LTM.

Depth of Processing and Age Differences.

PubMed

Kheirzadeh, Shiela; Pakzadian, Sarah Sadat

2016-10-01

The present article is aimed to investigate whether there are any differences between youngsters and adults in their working and long-term memory functioning. The theory of Depth of Processing (Craik and Lockhart in J Verbal Learning Verbal Behav 11:671-684, 1972) discusses the varying degrees of strengths of memory traces as the result of differential levels of processing on the retrieved input. Additionally, they claim that there are three levels of visual, auditory and semantic processes applied on the stimuli in the short-term memory leading to discrepancy in the durability of the memory traces and the later ease of recall and retrieval. In the present article, it is tried to demonstrate if there are evidences of more durable memory traces formed after semantic, visual and auditory processions of the incoming language data in two groups of (a) children in their language learning critical age and (b) youngsters who have passed the critical age period. The comparisons of the results made using two-way ANOVAs revealed the superiority of semantic processing for both age groups in recall, retention and consequently recognition of the new English vocabularies by EFL learners.

Three more semantic serial position functions and a SIMPLE explanation.

PubMed

Kelley, Matthew R; Neath, Ian; Surprenant, Aimée M

2013-05-01

There are innumerable demonstrations of serial position functions-with characteristic primacy and recency effects-in episodic tasks, but there are only a handful of such demonstrations in semantic memory tasks, and those demonstrations have used only two types of stimuli. Here, we provide three more examples of serial position functions when recalling from semantic memory. Participants were asked to reconstruct the order of (1) two cartoon theme song lyrics, (2) the seven Harry Potter books, and (3) two sets of movies, and all three demonstrations yielded conventional-looking serial position functions with primacy and recency effects. The data were well-fit by SIMPLE, a local distinctiveness model of memory that was originally designed to account for serial position effects in short- and long-term episodic memory. According to SIMPLE, serial position functions in both episodic and semantic memory tasks arise from the same type of processing: Items that are more separated from their close neighbors in psychological space at the time of recall will be better remembered. We argue that currently available evidence suggests that serial position functions observed when recalling items that are presumably in semantic memory arise because of the same processes as those observed when recalling items that are presumably in episodic memory.

The impact of intelligence on memory and executive functions of children with temporal lobe epilepsy: Methodological concerns with clinical relevance.

PubMed

Rzezak, Patricia; Guimarães, Catarina A; Guerreiro, Marilisa M; Valente, Kette D

2017-05-01

Patients with TLE are prone to have lower IQ scores than healthy controls. Nevertheless, the impact of IQ differences is not usually considered in studies that compared the cognitive functioning of children with and without epilepsy. This study aimed to determine the effect of using IQ as a covariate on memory and attentional/executive functions of children with TLE. Thirty-eight children and adolescents with TLE and 28 healthy controls paired as to age, gender, and sociodemographic factors were evaluated with a comprehensive neuropsychological battery for memory and executive functions. The authors conducted three analyses to verify the impact of IQ scores on the other cognitive domains. First, we compared performance on cognitive tests without controlling for IQ differences between groups. Second, we performed the same analyses, but we included IQ as a confounding factor. Finally, we evaluated the predictive value of IQ on cognitive functioning. Although patients had IQ score in the normal range, they showed lower IQ scores than controls (p = 0.001). When we did not consider IQ in the analyses, patients had worse performance in verbal and visual memory (short and long-term), semantic memory, sustained, divided and selective attention, mental flexibility and mental tracking for semantic information. By using IQ as a covariate, patients showed worse performance only in verbal memory (long-term), semantic memory, sustained and divided attention and in mental flexibility. IQ was a predictor factor of verbal and visual memory (immediate and delayed), working memory, mental flexibility and mental tracking for semantic information. Intelligence level had a significant impact on memory and executive functioning of children and adolescents with TLE without intellectual disability. This finding opens the discussion of whether IQ scores should be considered when interpreting the results of differences in cognitive performance of patients with epilepsy compared to healthy volunteers. Copyright © 2017 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

Long-Term Interference at the Semantic Level: Evidence from Blocked-Cyclic Picture Matching

ERIC Educational Resources Information Center

Wei, Tao; Schnur, Tatiana T.

2016-01-01

Processing semantically related stimuli creates interference across various domains of cognition, including language and memory. In this study, we identify the locus and mechanism of interference when retrieving meanings associated with words and pictures. Subjects matched a probe stimulus (e.g., cat) to its associated target picture (e.g., yarn)…

Reduced short-term memory capacity in Alzheimer's disease: the role of phonological, lexical, and semantic processing.

PubMed

Caza, Nicole; Belleville, Sylvie

2008-05-01

Individuals with Alzheimer's disease (AD) are often reported to have reduced verbal short-term memory capacity, typically attributed to their attention/executive deficits. However, these individuals also tend to show progressive impairment of semantic, lexical, and phonological processing which may underlie their low short-term memory capacity. The goals of this study were to assess the contribution of each level of representation (phonological, lexical, and semantic) to immediate serial recall performance in 18 individuals with AD, and to examine how these linguistic effects on short-term memory were modulated by their reduced capacity to manipulate information in short-term memory associated with executive dysfunction. Results showed that individuals with AD had difficulty recalling items that relied on phonological representations, which led to increased lexicality effects relative to the control group. This finding suggests that patients have a greater reliance on lexical/semantic information than controls, possibly to make up for deficits in retention and processing of phonological material. This lexical/semantic effect was not found to be significantly correlated with patients' capacity to manipulate verbal material in short-term memory, indicating that language processing and executive deficits may independently contribute to reducing verbal short-term memory capacity in AD.

The differential effects of ecstasy/polydrug use on executive components: shifting, inhibition, updating and access to semantic memory.

PubMed

Montgomery, Catharine; Fisk, John E; Newcombe, Russell; Murphy, Phillip N

2005-10-01

Recent theoretical models suggest that the central executive may not be a unified structure. The present study explored the nature of central executive deficits in ecstasy users. In study 1, 27 ecstasy users and 34 non-users were assessed using tasks to tap memory updating (computation span; letter updating) and access to long-term memory (a semantic fluency test and the Chicago Word Fluency Test). In study 2, 51 ecstasy users and 42 non-users completed tasks that assess mental set switching (number/letter and plus/minus) and inhibition (random letter generation). MANOVA revealed that ecstasy users performed worse on both tasks used to assess memory updating and on tasks to assess access to long-term memory (C- and S-letter fluency). However, notwithstanding the significant ecstasy group-related effects, indices of cocaine and cannabis use were also significantly correlated with most of the executive measures. Unexpectedly, in study 2, ecstasy users performed significantly better on the inhibition task, producing more letters than non-users. No group differences were observed on the switching tasks. Correlations between indices of ecstasy use and number of letters produced were significant. The present study provides further support for ecstasy/polydrug-related deficits in memory updating and in access to long-term memory. The surplus evident on the inhibition task should be treated with some caution, as this was limited to a single measure and has not been supported by our previous work.

The Episodic Buffer in Children with Intellectual Disabilities: An Exploratory Study

ERIC Educational Resources Information Center

Henry, Lucy A.

2010-01-01

Performance on three verbal measures (story recall, paired associated learning, category fluency) designed to assess the integration of long-term semantic and linguistic knowledge, phonological working memory and executive resources within the proposed "episodic buffer" of working memory (Baddeley, 2007) was assessed in children with intellectual…

The Ease of Language Understanding (ELU) model: theoretical, empirical, and clinical advances

PubMed Central

Rönnberg, Jerker; Lunner, Thomas; Zekveld, Adriana; Sörqvist, Patrik; Danielsson, Henrik; Lyxell, Björn; Dahlström, Örjan; Signoret, Carine; Stenfelt, Stefan; Pichora-Fuller, M. Kathleen; Rudner, Mary

2013-01-01

Working memory is important for online language processing during conversation. We use it to maintain relevant information, to inhibit or ignore irrelevant information, and to attend to conversation selectively. Working memory helps us to keep track of and actively participate in conversation, including taking turns and following the gist. This paper examines the Ease of Language Understanding model (i.e., the ELU model, Rönnberg, 2003; Rönnberg et al., 2008) in light of new behavioral and neural findings concerning the role of working memory capacity (WMC) in uni-modal and bimodal language processing. The new ELU model is a meaning prediction system that depends on phonological and semantic interactions in rapid implicit and slower explicit processing mechanisms that both depend on WMC albeit in different ways. It is based on findings that address the relationship between WMC and (a) early attention processes in listening to speech, (b) signal processing in hearing aids and its effects on short-term memory, (c) inhibition of speech maskers and its effect on episodic long-term memory, (d) the effects of hearing impairment on episodic and semantic long-term memory, and finally, (e) listening effort. New predictions and clinical implications are outlined. Comparisons with other WMC and speech perception models are made. PMID:23874273

Temporal lobe surgery in childhood and neuroanatomical predictors of long-term declarative memory outcome

PubMed Central

Skirrow, Caroline; Cross, J. Helen; Harrison, Sue; Cormack, Francesca; Harkness, William; Coleman, Rosie; Meierotto, Ellen; Gaiottino, Johanna; Vargha-Khadem, Faraneh

2015-01-01

The temporal lobes play a prominent role in declarative memory function, including episodic memory (memory for events) and semantic memory (memory for facts and concepts). Surgical resection for medication-resistant and well-localized temporal lobe epilepsy has good prognosis for seizure freedom, but is linked to memory difficulties in adults, especially when the removal is on the left side. Children may benefit most from surgery, because brain plasticity may facilitate post-surgical reorganization, and seizure cessation may promote cognitive development. However, the long-term impact of this intervention in children is not known. We examined memory function in 53 children (25 males, 28 females) who were evaluated for epilepsy surgery: 42 underwent unilateral temporal lobe resections (25 left, 17 right, mean age at surgery 13.8 years), 11 were treated only pharmacologically. Average follow-up was 9 years (range 5–15). Post-surgical change in visual and verbal episodic memory, and semantic memory at follow-up were examined. Pre- and post-surgical T1-weighted MRI brain scans were analysed to extract hippocampal and resection volumes, and evaluate post-surgical temporal lobe integrity. Language lateralization indices were derived from functional magnetic resonance imaging. There were no significant pre- to postoperative decrements in memory associated with surgery. In contrast, gains in verbal episodic memory were seen after right temporal lobe surgery, and visual episodic memory improved after left temporal lobe surgery, indicating a functional release in the unoperated temporal lobe after seizure reduction or cessation. Pre- to post-surgical change in memory function was not associated with any indices of brain structure derived from MRI. However, better verbal memory at follow-up was linked to greater post-surgical residual hippocampal volumes, most robustly in left surgical participants. Better semantic memory at follow-up was associated with smaller resection volumes and greater temporal pole integrity after left temporal surgery. Results were independent of post-surgical intellectual function and language lateralization. Our findings indicate post-surgical, hemisphere-dependent material-specific improvement in memory functions in the intact temporal lobe. However, outcome was linked to the anatomical integrity of the temporal lobe memory system, indicating that compensatory mechanisms are constrained by the amount of tissue which remains in the operated temporal lobe. Careful tailoring of resections for children undergoing epilepsy surgery may enhance long-term memory outcome. PMID:25392199

[Artificial intelligence meeting neuropsychology. Semantic memory in normal and pathological aging].

PubMed

Aimé, Xavier; Charlet, Jean; Maillet, Didier; Belin, Catherine

2015-03-01

Artificial intelligence (IA) is the subject of much research, but also many fantasies. It aims to reproduce human intelligence in its learning capacity, knowledge storage and computation. In 2014, the Defense Advanced Research Projects Agency (DARPA) started the restoring active memory (RAM) program that attempt to develop implantable technology to bridge gaps in the injured brain and restore normal memory function to people with memory loss caused by injury or disease. In another IA's field, computational ontologies (a formal and shared conceptualization) try to model knowledge in order to represent a structured and unambiguous meaning of the concepts of a target domain. The aim of these structures is to ensure a consensual understanding of their meaning and a univariant use (the same concept is used by all to categorize the same individuals). The first representations of knowledge in the AI's domain are largely based on model tests of semantic memory. This one, as a component of long-term memory is the memory of words, ideas, concepts. It is the only declarative memory system that resists so remarkably to the effects of age. In contrast, non-specific cognitive changes may decrease the performance of elderly in various events and instead report difficulties of access to semantic representations that affect the semantics stock itself. Some dementias, like semantic dementia and Alzheimer's disease, are linked to alteration of semantic memory. We propose in this paper, using the computational ontologies model, a formal and relatively thin modeling, in the service of neuropsychology: 1) for the practitioner with decision support systems, 2) for the patient as cognitive prosthesis outsourced, and 3) for the researcher to study semantic memory.

Motivated encoding selectively promotes memory for future inconsequential semantically-related events.

PubMed

Oyarzún, Javiera P; Packard, Pau A; de Diego-Balaguer, Ruth; Fuentemilla, Lluis

2016-09-01

Neurobiological models of long-term memory explain how memory for inconsequential events fades, unless these happen before or after other relevant (i.e., rewarding or aversive) or novel events. Recently, it has been shown in humans that retrospective and prospective memories are selectively enhanced if semantically related events are paired with aversive stimuli. However, it remains unclear whether motivating stimuli, as opposed to aversive, have the same effect in humans. Here, participants performed a three phase incidental encoding task where one semantic category was rewarded during the second phase. A memory test 24h after, but not immediately after encoding, revealed that memory for inconsequential items was selectively enhanced only if items from the same category had been previously, but not subsequently, paired with rewards. This result suggests that prospective memory enhancement of reward-related information requires, like previously reported for aversive memories, of a period of memory consolidation. The current findings provide the first empirical evidence in humans that the effects of motivated encoding are selectively and prospectively prolonged over time. Copyright © 2016 Elsevier Inc. All rights reserved.

The Construction of Semantic Memory: Grammar-Based Representations Learned from Relational Episodic Information

PubMed Central

Battaglia, Francesco P.; Pennartz, Cyriel M. A.

2011-01-01

After acquisition, memories underlie a process of consolidation, making them more resistant to interference and brain injury. Memory consolidation involves systems-level interactions, most importantly between the hippocampus and associated structures, which takes part in the initial encoding of memory, and the neocortex, which supports long-term storage. This dichotomy parallels the contrast between episodic memory (tied to the hippocampal formation), collecting an autobiographical stream of experiences, and semantic memory, a repertoire of facts and statistical regularities about the world, involving the neocortex at large. Experimental evidence points to a gradual transformation of memories, following encoding, from an episodic to a semantic character. This may require an exchange of information between different memory modules during inactive periods. We propose a theory for such interactions and for the formation of semantic memory, in which episodic memory is encoded as relational data. Semantic memory is modeled as a modified stochastic grammar, which learns to parse episodic configurations expressed as an association matrix. The grammar produces tree-like representations of episodes, describing the relationships between its main constituents at multiple levels of categorization, based on its current knowledge of world regularities. These regularities are learned by the grammar from episodic memory information, through an expectation-maximization procedure, analogous to the inside–outside algorithm for stochastic context-free grammars. We propose that a Monte-Carlo sampling version of this algorithm can be mapped on the dynamics of “sleep replay” of previously acquired information in the hippocampus and neocortex. We propose that the model can reproduce several properties of semantic memory such as decontextualization, top-down processing, and creation of schemata. PMID:21887143

Serial position effects in semantic memory: reconstructing the order of verses of hymns.

PubMed

Maylor, Elizabeth A

2002-12-01

Serial position effects (primacy and recency) have been consistently demonstrated in both short- and long-term episodic memory tasks. The search for corresponding effects in semantic memory tasks (e.g., reconstructing the order of U.S. presidents) has been confounded by factors such as differential exposure to stimuli. In the present study, the stimuli were six-verse hymns that would have been sung from the first to the last verse by churchgoers on numerous occasions. Participants were presented with the verses of each hymn in random order and were required to reconstruct the correct order. Primacy and recency effects were significantly more evident for churchgoers than for nonchurchgoers. Moreover, error gradients were steeper than chance for churchgoers but not for nonchurchgoers; in other words, churchgoers' errors were more likely to be close to the correct position than further away. These findings provide the first unequivocal demonstration of serial position effects in semantic memory.

Short theta burst stimulation to left frontal cortex prior to encoding enhances subsequent recognition memory

PubMed Central

Demeter, Elise; Mirdamadi, Jasmine L.; Meehan, Sean K.; Taylor, Stephan F.

2016-01-01

Deep semantic encoding of verbal stimuli can aid in later successful retrieval of those stimuli from long-term episodic memory. Evidence from numerous neuropsychological and neuroimaging experiments demonstrate regions in left prefrontal cortex, including left dorsolateral prefrontal cortex (DLPFC), are important for processes related to encoding. Here, we investigated the relationship between left DLPFC activity during encoding and successful subsequent memory with transcranial magnetic stimulation (TMS). In a pair of experiments using a 2-session within-subjects design, we stimulated either left DLPFC or a control region (Vertex) with a single 2-s train of short theta burst stimulation (sTBS) during a semantic encoding task and then gave participants a recognition memory test. We found that subsequent memory was enhanced on the day left DLPFC was stimulated, relative to the day Vertex was stimulated, and that DLPFC stimulation also increased participants’ confidence in their decisions during the recognition task. We also explored the time course of how long the effects of sTBS persisted. Our data suggest 2 s of sTBS to left DLPFC is capable of enhancing subsequent memory for items encoded up to 15 s following stimulation. Collectively, these data demonstrate sTBS is capable of enhancing long-term memory and provide evidence that TBS protocols are a potentially powerful tool for modulating cognitive function. PMID:27098772

Hemispheric asymmetries in discourse processing: evidence from false memories for lists and texts.

PubMed

Ben-Artzi, Elisheva; Faust, Miriam; Moeller, Edna

2009-01-01

Previous research suggests that the right hemisphere (RH) may contribute uniquely to discourse and text processing by activating and maintaining a wide range of meanings, including more distantly related meanings. The present study used the word-lists false memory paradigm [Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21, 803-814.] to examine the hypothesis that difference between the two cerebral hemispheres in discourse processing may be due, at least partly, to memory representations for implicit text-related semantic information. Specifically, we tested the susceptibility of the left hemisphere (LH) and RH to unpresented target words following the presentation of semantically related words appearing in either word lists or short texts. Findings showed that the RH produced more false alarms than the LH for unpresented target words following either word lists or texts. These findings reveal hemispheric differences in memory for semantically related information and suggest that RH advantage in long-term maintenance of a wide range of text-related word meanings may be one aspect of its unique contribution to the construction of a discourse model. The results support the RH coarse semantic coding theory [Beeman, M. (1998). Coarse semantic coding and discourse comprehension. In M. Beeman & C. Chiarello (Eds.), Right hemisphere language comprehension: Perspectives from cognitive neuroscience (pp. 255-284). Mahwah, NJ: Erlbaum.] and suggest that hemispheric differences in semantic processing during language comprehension extend also to verbal memory.

Consolidation of long-term memory: evidence and alternatives.

PubMed

Meeter, Martijn; Murre, Jaap M J

2004-11-01

Memory loss in retrograde amnesia has long been held to be larger for recent periods than for remote periods, a pattern usually referred to as the Ribot gradient. One explanation for this gradient is consolidation of long-term memories. Several computational models of such a process have shown how consolidation can explain characteristics of amnesia, but they have not elucidated how consolidation must be envisaged. Here findings are reviewed that shed light on how consolidation may be implemented in the brain. Moreover, consolidation is contrasted with alternative theories of the Ribot gradient. Consolidation theory, multiple trace theory, and semantization can all handle some findings well but not others. Conclusive evidence for or against consolidation thus remains to be found.

Episodic and Semantic Memories of a Residential Environmental Education Program

ERIC Educational Resources Information Center

Knapp, Doug; Benton, Gregory M.

2006-01-01

This study used a phenomenological approach to investigate the recollections of participants of an environmental education (EE) residential program. Ten students who participated in a residential EE program in the fall of 2001 were interviewed in the fall of 2002. Three major themes relating to the participants' long-term memory of the residential…

Memory for environmental sounds in sighted, congenitally blind and late blind adults: evidence for cross-modal compensation.

PubMed

Röder, Brigitte; Rösler, Frank

2003-10-01

Several recent reports suggest compensatory performance changes in blind individuals. It has, however, been argued that the lack of visual input leads to impoverished semantic networks resulting in the use of data-driven rather than conceptual encoding strategies on memory tasks. To test this hypothesis, congenitally blind and sighted participants encoded environmental sounds either physically or semantically. In the recognition phase, both conceptually as well as physically distinct and physically distinct but conceptually highly related lures were intermixed with the environmental sounds encountered during study. Participants indicated whether or not they had heard a sound in the study phase. Congenitally blind adults showed elevated memory both after physical and semantic encoding. After physical encoding blind participants had lower false memory rates than sighted participants, whereas the false memory rates of sighted and blind participants did not differ after semantic encoding. In order to address the question if compensatory changes in memory skills are restricted to critical periods during early childhood, late blind adults were tested with the same paradigm. When matched for age, they showed similarly high memory scores as the congenitally blind. These results demonstrate compensatory performance changes in long-term memory functions due to the loss of a sensory system and provide evidence for high adaptive capabilities of the human cognitive system.

Only time will tell - why temporal information is essential for our neuroscientific understanding of semantics.

PubMed

Hauk, Olaf

2016-08-01

Theoretical developments about the nature of semantic representations and processes should be accompanied by a discussion of how these theories can be validated on the basis of empirical data. Here, I elaborate on the link between theory and empirical research, highlighting the need for temporal information in order to distinguish fundamental aspects of semantics. The generic point that fast cognitive processes demand fast measurement techniques has been made many times before, although arguably more often in the psychophysiological community than in the metabolic neuroimaging community. Many reviews on the neuroscience of semantics mostly or even exclusively focus on metabolic neuroimaging data. Following an analysis of semantics in terms of the representations and processes involved, I argue that fundamental theoretical debates about the neuroscience of semantics can only be concluded on the basis of data with sufficient temporal resolution. Any "semantic effect" may result from a conflation of long-term memory representations, retrieval and working memory processes, mental imagery, and episodic memory. This poses challenges for all neuroimaging modalities, but especially for those with low temporal resolution. It also throws doubt on the usefulness of contrasts between meaningful and meaningless stimuli, which may differ on a number of semantic and non-semantic dimensions. I will discuss the consequences of this analysis for research on the role of convergence zones or hubs and distributed modal brain networks, top-down modulation of task and context as well as interactivity between levels of the processing hierarchy, for example in the framework of predictive coding.

Explaining Semantic Short-Term Memory Deficits: Evidence for the Critical Role of Semantic Control

ERIC Educational Resources Information Center

Hoffman, Paul; Jefferies, Elizabeth; Lambon Ralph, Matthew A.

2011-01-01

Patients with apparently selective short-term memory (STM) deficits for semantic information have played an important role in developing multi-store theories of STM and challenge the idea that verbal STM is supported by maintaining activation in the language system. We propose that semantic STM deficits are not as selective as previously thought…

Auditory Distraction in Semantic Memory: A Process-Based Approach

ERIC Educational Resources Information Center

Marsh, John E.; Hughes, Robert W.; Jones, Dylan M.

2008-01-01

Five experiments demonstrate auditory-semantic distraction in tests of memory for semantic category-exemplars. The effects of irrelevant sound on category-exemplar recall are shown to be functionally distinct from those found in the context of serial short-term memory by showing sensitivity to: The lexical-semantic, rather than acoustic,…

Memory strategy training in children with cerebral infarcts related to sickle cell disease.

PubMed

Yerys, Benjamin E; White, Desirée A; Salorio, Cynthia F; McKinstry, Robert; Moinuddin, Asif; DeBaun, Michael

2003-06-01

Cerebral infarcts occur in approximately 30% of children with sickle cell disease (SCD), but little information exists regarding remediation of associated cognitive deficits. The authors examined the benefits of training children with infarcts to use memory strategies. Six children with SCD-related infarcts received academic tutoring; three of these children received additional training in memory strategies (silent rehearsal to facilitate short-term memory and semantic organization to facilitate long-term memory). The performance of children receiving strategy training appeared to improve more than that of children receiving only tutoring. Memory in children with SCD-related infarcts may be enhanced through strategy training.

The Impact of Semantic Impairment on Verbal Short-Term Memory in Stroke Aphasia and Semantic Dementia: A Comparative Study

ERIC Educational Resources Information Center

Jefferies, Elizabeth; Hoffman, Paul; Jones, Roy; Lambon Ralph, Matthew A.

2008-01-01

This study presents the first direct comparison of immediate serial recall in semantic dementia (SD) and transcortical sensory aphasia (TSA). Previous studies of the effect of semantic impairment on verbal short-term memory (STM) have led to important theoretical advances. However, different conclusions have been drawn from these two groups. This…

Interdependence of episodic and semantic memory: evidence from neuropsychology.

PubMed

Greenberg, Daniel L; Verfaellie, Mieke

2010-09-01

Tulving's (1972) theory of memory draws a distinction between general knowledge (semantic memory) and memory for events (episodic memory). Neuropsychological studies have generally examined each type of memory in isolation, but theorists have long argued that these two forms of memory are interdependent. Here we review several lines of neuropsychological research that have explored the interdependence of episodic and semantic memory. The studies show that these forms of memory can affect each other both at encoding and at retrieval. We suggest that theories of memory should be revised to account for all of the interdependencies between episodic and semantic memory; they should also incorporate forms of memory that do not fit neatly into either category.

Interdependence of episodic and semantic memory: Evidence from neuropsychology

PubMed Central

GREENBERG, DANIEL L.; VERFAELLIE, MIEKE

2010-01-01

Tulving's (1972) theory of memory draws a distinction between general knowledge (semantic memory) and memory for events (episodic memory). Neuropsychological studies have generally examined each type of memory in isolation, but theorists have long argued that these two forms of memory are interdependent. Here we review several lines of neuropsychological research that have explored the interdependence of episodic and semantic memory. The studies show that these forms of memory can affect each other both at encoding and at retrieval. We suggest that theories of memory should be revised to account for all of the interdependencies between episodic and semantic memory; they should also incorporate forms of memory that do not fit neatly into either category. PMID:20561378

Autobiographical Memory Deficits in Alcohol-Dependent Patients with Short- and Long-Term Abstinence.

PubMed

Nandrino, Jean-Louis; El Haj, Mohamad; Torre, Julie; Naye, Delphine; Douchet, Helyette; Danel, Thierry; Cottençin, Oliver

2016-04-01

Autobiographical memory (AM) enables the storage and retrieval of life experiences that allow individuals to build their sense of identity. Several AM impairments have been described in patients with alcohol abuse disorders without assessing whether such deficits can be recovered. This cross-sectional study aimed to identify whether the semantic (SAM) and episodic (EAM) dimensions of AM are affected in individuals with alcohol dependence after short-term abstinence (STA) or long-term abstinence (LTA). A second aim of this study was to examine the factors that could disrupt the efficiency of semantic and episodic AM (the impact of depression severity, cognitive functions, recent or early traumatic events, and drinking history variables). After clinical and cognitive evaluations (alcohol consumption, depression, anxiety, IQ, memory performance), AM was assessed with the Autobiographical Memory Interview in patients with recent (between 4 and 6 weeks) and longer (at least 6 months) abstinence. Participants were asked to retrieve the number and nature of traumatic or painful life experiences in recent or early life periods (using the Childhood Traumatic Events Scale). The 2 abstinent groups had lower global EAM and SAM scores than the control group. These scores were comparable for both abstinent groups. For childhood events, no significant differences were observed in SAM for both groups compared with control participants. For early adulthood and recent events, both STA and LTA groups had lower scores on both SAM and EAM. Moreover, there was a negative correlation between the length of substance consumption and SAM scores. This study highlighted a specific AM disorder in both episodic and semantic dimensions. These deficits remained after 6 months of abstinence. This AM impairment may be explained by compromised encoding and consolidation of memories during bouts of drinking. Copyright © 2016 by the Research Society on Alcoholism.

Supervised guiding long-short term memory for image caption generation based on object classes

NASA Astrophysics Data System (ADS)

Wang, Jian; Cao, Zhiguo; Xiao, Yang; Qi, Xinyuan

2018-03-01

The present models of image caption generation have the problems of image visual semantic information attenuation and errors in guidance information. In order to solve these problems, we propose a supervised guiding Long Short Term Memory model based on object classes, named S-gLSTM for short. It uses the object detection results from R-FCN as supervisory information with high confidence, and updates the guidance word set by judging whether the last output matches the supervisory information. S-gLSTM learns how to extract the current interested information from the image visual se-mantic information based on guidance word set. The interested information is fed into the S-gLSTM at each iteration as guidance information, to guide the caption generation. To acquire the text-related visual semantic information, the S-gLSTM fine-tunes the weights of the network through the back-propagation of the guiding loss. Complementing guidance information at each iteration solves the problem of visual semantic information attenuation in the traditional LSTM model. Besides, the supervised guidance information in our model can reduce the impact of the mismatched words on the caption generation. We test our model on MSCOCO2014 dataset, and obtain better performance than the state-of-the- art models.

Structured Semantic Knowledge Can Emerge Automatically from Predicting Word Sequences in Child-Directed Speech

PubMed Central

Huebner, Philip A.; Willits, Jon A.

2018-01-01

Previous research has suggested that distributional learning mechanisms may contribute to the acquisition of semantic knowledge. However, distributional learning mechanisms, statistical learning, and contemporary “deep learning” approaches have been criticized for being incapable of learning the kind of abstract and structured knowledge that many think is required for acquisition of semantic knowledge. In this paper, we show that recurrent neural networks, trained on noisy naturalistic speech to children, do in fact learn what appears to be abstract and structured knowledge. We trained two types of recurrent neural networks (Simple Recurrent Network, and Long Short-Term Memory) to predict word sequences in a 5-million-word corpus of speech directed to children ages 0–3 years old, and assessed what semantic knowledge they acquired. We found that learned internal representations are encoding various abstract grammatical and semantic features that are useful for predicting word sequences. Assessing the organization of semantic knowledge in terms of the similarity structure, we found evidence of emergent categorical and hierarchical structure in both models. We found that the Long Short-term Memory (LSTM) and SRN are both learning very similar kinds of representations, but the LSTM achieved higher levels of performance on a quantitative evaluation. We also trained a non-recurrent neural network, Skip-gram, on the same input to compare our results to the state-of-the-art in machine learning. We found that Skip-gram achieves relatively similar performance to the LSTM, but is representing words more in terms of thematic compared to taxonomic relations, and we provide reasons why this might be the case. Our findings show that a learning system that derives abstract, distributed representations for the purpose of predicting sequential dependencies in naturalistic language may provide insight into emergence of many properties of the developing semantic system. PMID:29520243

Semantic and Phonological Loop Effects on Verbal Working Memory in Middle-Age Adults with Mental Retardation

ERIC Educational Resources Information Center

Kittler, Phyllis; Krinsky-McHale, Sharon J.; Devenny, Darlynne A.

2004-01-01

Semantic and phonological loop effects on verbal working memory were examined among middle-age adults with Down syndrome and those with unspecified mental retardation in the context of Baddeley's working memory model. Recall was poorer for phonologically similar, semantically similar, and long words compared to recall of dissimilar short words.…

Neural mechanisms underlying the facilitation of naming in aphasia using a semantic task: an fMRI study

PubMed Central

2012-01-01

Background Previous attempts to investigate the effects of semantic tasks on picture naming in both healthy controls and people with aphasia have typically been confounded by inclusion of the phonological word form of the target item. As a result, it is difficult to isolate any facilitatory effects of a semantically-focused task to either lexical-semantic or phonological processing. This functional magnetic resonance imaging (fMRI) study examined the neurological mechanisms underlying short-term (within minutes) and long-term (within days) facilitation of naming from a semantic task that did not include the phonological word form, in both participants with aphasia and age-matched controls. Results Behavioral results showed that a semantic task that did not include the phonological word form can successfully facilitate subsequent picture naming in both healthy controls and individuals with aphasia. The whole brain neuroimaging results for control participants identified a repetition enhancement effect in the short-term, with modulation of activity found in regions that have not traditionally been associated with semantic processing, such as the right lingual gyrus (extending to the precuneus) and the left inferior occipital gyrus (extending to the fusiform gyrus). In contrast, the participants with aphasia showed significant differences in activation over both the short- and the long-term for facilitated items, predominantly within either left hemisphere regions linked to semantic processing or their right hemisphere homologues. Conclusions For control participants in this study, the short-lived facilitation effects of a prior semantic task that did not include the phonological word form were primarily driven by object priming and episodic memory mechanisms. However, facilitation effects appeared to engage a predominantly semantic network in participants with aphasia over both the short- and the long-term. The findings of the present study also suggest that right hemisphere involvement may be supportive rather than maladaptive, and that a large distributed perisylvian network in both cerebral hemispheres supports the facilitation of naming in individuals with aphasia. PMID:22882806

Functional neuroanatomy of remote episodic, semantic and spatial memory: a unified account based on multiple trace theory

PubMed Central

Moscovitch, Morris; Rosenbaum, R Shayna; Gilboa, Asaf; Addis, Donna Rose; Westmacott, Robyn; Grady, Cheryl; McAndrews, Mary Pat; Levine, Brian; Black, Sandra; Winocur, Gordon; Nadel, Lynn

2005-01-01

We review lesion and neuroimaging evidence on the role of the hippocampus, and other structures, in retention and retrieval of recent and remote memories. We examine episodic, semantic and spatial memory, and show that important distinctions exist among different types of these memories and the structures that mediate them. We argue that retention and retrieval of detailed, vivid autobiographical memories depend on the hippocampal system no matter how long ago they were acquired. Semantic memories, on the other hand, benefit from hippocampal contribution for some time before they can be retrieved independently of the hippocampus. Even semantic memories, however, can have episodic elements associated with them that continue to depend on the hippocampus. Likewise, we distinguish between experientially detailed spatial memories (akin to episodic memory) and more schematic memories (akin to semantic memory) that are sufficient for navigation but not for re-experiencing the environment in which they were acquired. Like their episodic and semantic counterparts, the former type of spatial memory is dependent on the hippocampus no matter how long ago it was acquired, whereas the latter can survive independently of the hippocampus and is represented in extra-hippocampal structures. In short, the evidence reviewed suggests strongly that the function of the hippocampus (and possibly that of related limbic structures) is to help encode, retain, and retrieve experiences, no matter how long ago the events comprising the experience occurred, and no matter whether the memories are episodic or spatial. We conclude that the evidence favours a multiple trace theory (MTT) of memory over two other models: (1) traditional consolidation models which posit that the hippocampus is a time-limited memory structure for all forms of memory; and (2) versions of cognitive map theory which posit that the hippocampus is needed for representing all forms of allocentric space in memory. PMID:16011544

Functional neuroanatomy of remote episodic, semantic and spatial memory: a unified account based on multiple trace theory.

PubMed

Moscovitch, Morris; Rosenbaum, R Shayna; Gilboa, Asaf; Addis, Donna Rose; Westmacott, Robyn; Grady, Cheryl; McAndrews, Mary Pat; Levine, Brian; Black, Sandra; Winocur, Gordon; Nadel, Lynn

2005-07-01

We review lesion and neuroimaging evidence on the role of the hippocampus, and other structures, in retention and retrieval of recent and remote memories. We examine episodic, semantic and spatial memory, and show that important distinctions exist among different types of these memories and the structures that mediate them. We argue that retention and retrieval of detailed, vivid autobiographical memories depend on the hippocampal system no matter how long ago they were acquired. Semantic memories, on the other hand, benefit from hippocampal contribution for some time before they can be retrieved independently of the hippocampus. Even semantic memories, however, can have episodic elements associated with them that continue to depend on the hippocampus. Likewise, we distinguish between experientially detailed spatial memories (akin to episodic memory) and more schematic memories (akin to semantic memory) that are sufficient for navigation but not for re-experiencing the environment in which they were acquired. Like their episodic and semantic counterparts, the former type of spatial memory is dependent on the hippocampus no matter how long ago it was acquired, whereas the latter can survive independently of the hippocampus and is represented in extra-hippocampal structures. In short, the evidence reviewed suggests strongly that the function of the hippocampus (and possibly that of related limbic structures) is to help encode, retain, and retrieve experiences, no matter how long ago the events comprising the experience occurred, and no matter whether the memories are episodic or spatial. We conclude that the evidence favours a multiple trace theory (MTT) of memory over two other models: (1) traditional consolidation models which posit that the hippocampus is a time-limited memory structure for all forms of memory; and (2) versions of cognitive map theory which posit that the hippocampus is needed for representing all forms of allocentric space in memory.

Hemispheric specialization in selective attention and short-term memory: a fine-coarse model of left- and right-ear disadvantages

PubMed Central

Marsh, John E.; Pilgrim, Lea K.; Sörqvist, Patrik

2013-01-01

Serial short-term memory is impaired by irrelevant sound, particularly when the sound changes acoustically. This acoustic effect is larger when the sound is presented to the left compared to the right ear (a left-ear disadvantage). Serial memory appears relatively insensitive to distraction from the semantic properties of a background sound. In contrast, short-term free recall of semantic-category exemplars is impaired by the semantic properties of background speech and is relatively insensitive to the sound's acoustic properties. This semantic effect is larger when the sound is presented to the right compared to the left ear (a right-ear disadvantage). In this paper, we outline a speculative neurocognitive fine-coarse model of these hemispheric differences in relation to short-term memory and selective attention, and explicate empirical directions in which this model can be critically evaluated. PMID:24399988

Argentines' collective memories of the military Junta of 1976: differences and similarities across generations and ideology.

PubMed

Muller, Felipe; Bermejo, Federico; Hirst, William

2016-08-01

Although memories about a nation's past usually are semantic in nature, a distinction needs to be made between lived and distant semantic collective memories. The former refers to memories of community-relevant events occurring during the lifetime of the rememberer, whereas the latter to memories of distant events. Does the content of lived and distant semantic collective memories differ? Employing both free and cued recall, we examined the memories of younger and older Argentines of the Military Junta of 1976. We also examined the effects of political ideology. Content analysis indicated that (1) lived semantic collective memories were more likely to contain personal recollections than distant semantic collective memories, even though those with distant semantic collective memories could have incorporated memories of the parent's personal experience in their recollections, (2) lived semantic collective memories contained more causal statements, and (3) those on the Right with distant semantic collective memories were more likely to claim that they "Don't know" or offer positive accounts of the Junta, suggesting a need to "defend" the reputation of those on the Right. The results are discussed in terms of the goals and plans different generations might have when recollecting their nation's past.

Semantic amnesia without dementia: documentation of a case.

PubMed

Rusconi, M L; Zago, S; Basso, A

1997-06-01

We described the case of a patient affected by a progressive semantic memory disorder associated with prevalent temporal lobe atrophy. This deficit seems to be "pure" in the sense that it has not been found to overlap with other cognitive deficits (intellectual, linguistic, perceptual, visuo-spatial etc.) for a long time. Furthermore, despite his impaired semantic knowledge, the autobiographical memory of the patient was largely intact. This case therefore represents a form of "semantic amnesia" without dementia, and supports the hypothesis that there is a partial distinction between "semantic" and "episodic" memory.

Newly-acquired words are more phonologically robust in verbal short-term memory when they have associated semantic representations.

PubMed

Savill, Nicola; Ellis, Andrew W; Jefferies, Elizabeth

2017-04-01

Verbal short-term memory (STM) is a crucial cognitive function central to language learning, comprehension and reasoning, yet the processes that underlie this capacity are not fully understood. In particular, although STM primarily draws on a phonological code, interactions between long-term phonological and semantic representations might help to stabilise the phonological trace for words ("semantic binding hypothesis"). This idea was first proposed to explain the frequent phoneme recombination errors made by patients with semantic dementia when recalling words that are no longer fully understood. However, converging evidence in support of semantic binding is scant: it is unusual for studies of healthy participants to examine serial recall at the phoneme level and also it is difficult to separate the contribution of phonological-lexical knowledge from effects of word meaning. We used a new method to disentangle these influences in healthy individuals by training new 'words' with or without associated semantic information. We examined phonological coherence in immediate serial recall (ISR), both immediately and the day after training. Trained items were more likely to be recalled than novel nonwords, confirming the importance of phonological-lexical knowledge, and items with semantic associations were also produced more accurately than those with no meaning, at both time points. For semantically-trained items, there were fewer phoneme ordering and identity errors, and consequently more complete target items were produced in both correct and incorrect list positions. These data show that lexical-semantic knowledge improves the robustness of verbal STM at the sub-item level, even when the effect of phonological familiarity is taken into account. Copyright © 2016 Elsevier Ltd. All rights reserved.

On the Existence of Semantic Working Memory: Evidence for Direct Semantic Maintenance

ERIC Educational Resources Information Center

Shivde, Geeta; Anderson, Michael C.

2011-01-01

Despite widespread acknowledgment of the importance of online semantic maintenance, there has been astonishingly little work that clearly establishes this construct. We review the extant work relevant to short-term retention of meaning and show that, although consistent with semantic working memory, most data can be accommodated in other ways.…

The relationships of 'ecstasy' (MDMA) and cannabis use to impaired executive inhibition and access to semantic long-term memory.

PubMed

Murphy, Philip N; Erwin, Philip G; Maciver, Linda; Fisk, John E; Larkin, Derek; Wareing, Michelle; Montgomery, Catharine; Hilton, Joanne; Tames, Frank J; Bradley, Belinda; Yanulevitch, Kate; Ralley, Richard

2011-10-01

This study aimed to examine the relationship between the consumption of ecstasy (3,4-methylenedioxymethamphetamine (MDMA)) and cannabis, and performance on the random letter generation task which generates dependent variables drawing upon executive inhibition and access to semantic long-term memory (LTM). The participant group was a between-participant independent variable with users of both ecstasy and cannabis (E/C group, n = 15), users of cannabis but not ecstasy (CA group, n = 13) and controls with no exposure to these drugs (CO group, n = 12). Dependent variables measured violations of randomness: number of repeat sequences, number of alphabetical sequences (both drawing upon inhibition) and redundancy (drawing upon access to semantic LTM). E/C participants showed significantly higher redundancy than CO participants but did not differ from CA participants. There were no significant effects for the other dependent variables. A regression model comprising intelligence measures and estimates of ecstasy and cannabis consumption predicted redundancy scores, but only cannabis consumption contributed significantly to this prediction. Impaired access to semantic LTM may be related to cannabis consumption, although the involvement of ecstasy and other stimulant drugs cannot be excluded here. Executive inhibitory functioning, as measured by the random letter generation task, is unrelated to ecstasy and cannabis consumption. Copyright © 2011 John Wiley & Sons, Ltd.

Behavioural and magnetoencephalographic evidence for the interaction between semantic and episodic memory in healthy elderly subjects.

PubMed

La Corte, Valentina; Dalla Barba, Gianfranco; Lemaréchal, Jean-Didier; Garnero, Line; George, Nathalie

2012-10-01

The relationship between episodic and semantic memory systems has long been debated. Some authors argue that episodic memory is contingent on semantic memory (Tulving 1984), while others postulate that both systems are independent since they can be selectively damaged (Squire 1987). The interaction between these memory systems is particularly important in the elderly, since the dissociation of episodic and semantic memory defects characterize different aging-related pathologies. Here, we investigated the interaction between semantic knowledge and episodic memory processes associated with faces in elderly subjects using an experimental paradigm where the semantic encoding of famous and unknown faces was compared to their episodic recognition. Results showed that the level of semantic awareness of items affected the recognition of those items in the episodic memory task. Event-related magnetic fields confirmed this interaction between episodic and semantic memory: ERFs related to the old/new effect during the episodic task were markedly different for famous and unknown faces. The old/new effect for famous faces involved sustained activities maximal over right temporal sensors, showing a spatio-temporal pattern partly similar to that found for famous versus unknown faces during the semantic task. By contrast, an old/new effect for unknown faces was observed on left parieto-occipital sensors. These findings suggest that the episodic memory for famous faces activated the retrieval of stored semantic information, whereas it was based on items' perceptual features for unknown faces. Overall, our results show that semantic information interfered markedly with episodic memory processes and suggested that the neural substrates of these two memory systems overlap.

The Relationship between Semantic Short-Term Memory and Immediate Serial Recall of Known and Unknown Words and Nonwords: Data from Two Chinese Individuals with Aphasia

ERIC Educational Resources Information Center

Wong, Winsy; Low, Sam-Po

2008-01-01

The present study investigated verbal recall of semantically preserved and degraded words and nonwords by taking into consideration the status of one's semantic short-term memory (STM). Two experiments were conducted on 2 Chinese individuals with aphasia. The first experiment showed that they had largely preserved phonological processing abilities…

Relations between Short-term Memory Deficits, Semantic Processing, and Executive Function

PubMed Central

Allen, Corinne M.; Martin, Randi C.; Martin, Nadine

2012-01-01

Background Previous research has suggested separable short-term memory (STM) buffers for the maintenance of phonological and lexical-semantic information, as some patients with aphasia show better ability to retain semantic than phonological information and others show the reverse. Recently, researchers have proposed that deficits to the maintenance of semantic information in STM are related to executive control abilities. Aims The present study investigated the relationship of executive function abilities with semantic and phonological short-term memory (STM) and semantic processing in such patients, as some previous research has suggested that semantic STM deficits and semantic processing abilities are critically related to specific or general executive function deficits. Method and Procedures 20 patients with aphasia and STM deficits were tested on measures of short-term retention, semantic processing, and both complex and simple executive function tasks. Outcome and Results In correlational analyses, we found no relation between semantic STM and performance on simple or complex executive function tasks. In contrast, phonological STM was related to executive function performance in tasks that had a verbal component, suggesting that performance in some executive function tasks depends on maintaining or rehearsing phonological codes. Although semantic STM was not related to executive function ability, performance on semantic processing tasks was related to executive function, perhaps due to similar executive task requirements in both semantic processing and executive function tasks. Conclusions Implications for treatment and interpretations of executive deficits are discussed. PMID:22736889

The role of semantically related distractors during encoding and retrieval of words in long-term memory.

PubMed

Meade, Melissa E; Fernandes, Myra A

2016-07-01

We examined the influence of divided attention (DA) on recognition of words when the concurrent task was semantically related or unrelated to the to-be-recognised target words. Participants were asked to either study or retrieve a target list of semantically related words while simultaneously making semantic decisions (i.e., size judgements) to another set of related or unrelated words heard concurrently. We manipulated semantic relatedness of distractor to target words, and whether DA occurred during the encoding or retrieval phase of memory. Recognition accuracy was significantly diminished relative to full attention, following DA conditions at encoding, regardless of relatedness of distractors to study words. However, response times (RTs) were slower with related compared to unrelated distractors. Similarly, under DA at retrieval, recognition RTs were slower when distractors were semantically related than unrelated to target words. Unlike the effect from DA at encoding, recognition accuracy was worse under DA at retrieval when the distractors were related compared to unrelated to the target words. Results suggest that availability of general attentional resources is critical for successful encoding, whereas successful retrieval is particularly reliant on access to a semantic code, making it sensitive to related distractors under DA conditions.

[Memory and brain--neurobiological correlates of memory disturbances].

PubMed

Calabrese, P; Markowitsch, H J

2003-04-01

A differentiation of memory is possible on the basis of chronological and contents-related aspects. Furthermore, it is possible to make process-specific subdivisions (encoding, transfer, consolidation, retrieval). The time-related division on the one hand refers to the general differentiation into short-term and long-term memory, and, on the other, to that between anterograde and retrograde memory ("new" and "old memory"; measured from a given time point, usually that when brain damage occurred). Anterograde memory means the successful encoding and storing of new information; retrograde the ability to retrieve successfully acquired and/or stored information. On the contents-based level, memory can be divided into five basic long-term systems--episodic memory, the knowledge system, perceptual, procedural and the priming form of memory. Neural correlates for these divisions are discussed with special emphasis of the episodic and the knowledge systems, based both on normal individuals and brain-damaged subjects. It is argued that structures of the limbic system are important for encoding of information and for its transfer into long-term memory. For this, two independent, but interacting memory circuits are proposed--one of them controlling and integrating primarily the emotional, and the other primarily the cognitive components of newly incoming information. For information storage principally neocortical structures are regarded as important and for the recall of information from the episodic and semantic memory systems the combined action of portions of prefrontal and anterior temporal regions is regarded as essential. Within this fronto-temporal agglomerate, a moderate hemispheric-specificity is assumed to exist with the right-hemispheric combination being mainly engaged in episodic memory retrieval and the left-hemispheric in that of semantic information. Evidence for this specialization comes from the results from focally brain-damaged patients as well as from that functional brain imaging in normal human subjects. Comparing results from imaging studies in memory disturbed patients with brain damage and from patients with a psychiatric diagnosis (e. g., psychogenic amnesia) revealed that both patient groups demonstrate comparable metabolic changes on the brain level. It can therefore be concluded that in neurological patients distinct, identifiable tissue damage is existent, while in psychiatric patients changes in the brain's biochemistry (release of stress hormones, and transmitters) constitute the physiological bases for the memory disturbances.

[Physiopathology of autobiographical memory in aging: episodic and semantic distinction, clinical findings and neuroimaging studies].

PubMed

Piolino, Pascale; Martinelli, Pénélope; Viard, Armelle; Noulhiane, Marion; Eustache, Francis; Desgranges, Béatrice

2010-01-01

From an early age, autobiographical memory models our feeling of identity and continuity. It grows throughout lifetime with our experiences and is built up from general self-knowledge and specific memories. The study of autobiographical memory depicts the dynamic and reconstructive features of this type of long-term memory, combining both semantic and episodic aspects, its strength and fragility. In this article, we propose to illustrate the properties of autobiographical memory from the field of cognitive psychology, neuropsychology and neuroimaging research through the analysis of the mechanisms of disturbance in normal and Alzheimer's disease. We show that the cognitive and neural bases of autobiographical memory are distinct in both cases. In normal aging, autobiographical memory retrieval is mainly dependent on frontal/executive function and on sense of reexperiencing specific context connected to hippocampal regions regardless of memory remoteness. In Alzheimer's disease, autobiographical memory deficit, characterized by a Ribot's temporal gradient, is connected to different regions according to memory remoteness. Our functional neuroimaging results suggest that patients at the early stage can compensate for their massive deficit of episodic recent memories correlated to hippocampal alteration with over general remote memories related to prefrontal regions. On the whole, the research findings allowed initiating new autobiographical memory studies by comparing normal and pathological aging and developing cognitive methods of memory rehabilitation in patients based on preserved personal semantic capacity. © Société de Biologie, 2010.

The Hippocampus Remains Activated over the Long Term for the Retrieval of Truly Episodic Memories

PubMed Central

Harand, Caroline; Bertran, Françoise; La Joie, Renaud; Landeau, Brigitte; Mézenge, Florence; Desgranges, Béatrice; Peigneux, Philippe; Eustache, Francis; Rauchs, Géraldine

2012-01-01

The role of the hippocampus in declarative memory consolidation is a matter of intense debate. We investigated the neural substrates of memory retrieval for recent and remote information using functional magnetic resonance imaging (fMRI). 18 young, healthy participants learned a series of pictures. Then, during two fMRI recognition sessions, 3 days and 3 months later, they had to determine whether they recognized or not each picture using the “Remember/Know” procedure. Presentation of the same learned images at both delays allowed us to track the evolution of memories and distinguish consistently episodic memories from those that were initially episodic and then became familiar or semantic over time and were retrieved without any contextual detail. Hippocampal activation decreased over time for initially episodic, later semantic memories, but remained stable for consistently episodic ones, at least in its posterior part. For both types of memories, neocortical activations were observed at both delays, notably in the ventromedial prefrontal and anterior cingulate cortices. These activations may reflect a gradual reorganization of memory traces within neural networks. Our data indicate maintenance and strengthening of hippocampal and cortico-cortical connections in the consolidation and retrieval of episodic memories over time, in line with the Multiple Trace theory (Nadel and Moscovitch, 1997). At variance, memories becoming semantic over time consolidate through strengthening of cortico-cortical connections and progressive disengagement of the hippocampus. PMID:22937055

Visual Information-Processing in the Perception of Features and Objects

DTIC Science & Technology

1989-01-05

or nodes in a semantic memory network, whereas recall and recognition depend on separate episodic memory traces. In our experiment, we used the same...problem for the account in terms of the separation of episodic from semantic memory , since no pre- existing representations of our line patterns were... semantic memory : amnesic patients were thought to have lost the ability to lay down (or retrieve) episodic traces of autobiographical events, but had

Verbal Short-Term Memory Deficits in Chinese Children with Dyslexia may not be a Problem with the Activation of Phonological Representations.

PubMed

Zhao, Jing; Yang, Yang; Song, Yao-Wu; Bi, Hong-Yan

2015-11-01

This study explored the underlying mechanism of the verbal short-term memory deficit in Chinese children with developmental dyslexia. Twenty-four children with dyslexia and 28 age-matched normal readers participated in the study. They were required to memorize a visually presented series of six Chinese characters and identify them from a list also including code-specific distracters and non-code-specific distracters. Error rates were recorded and were higher for code-specific distracters in all three conditions, revealing phonological, visual, and semantic similarity effects respectively. Group comparisons showed a stronger phonological similarity effect in dyslexic group, suggesting intact activation of phonological representations of target characters. Children with dyslexia also exhibited a greater semantic similarity effect, revealing stronger activation of semantic representations, while visual similarity effects were equivalent to controls. These results suggest that the verbal short-term memory deficit in Chinese dyslexics might not stem from insufficient activation of phonological information. Based the semantic activation of target characters in dyslexics is greater than in controls, it is possible that the memory deficit of dyslexia is related with deficient inhibition of target semantic representations in short-term memory. Copyright © 2015 John Wiley & Sons, Ltd.

Knowledge acquisition is governed by striatal prediction errors.

PubMed

Pine, Alex; Sadeh, Noa; Ben-Yakov, Aya; Dudai, Yadin; Mendelsohn, Avi

2018-04-26

Discrepancies between expectations and outcomes, or prediction errors, are central to trial-and-error learning based on reward and punishment, and their neurobiological basis is well characterized. It is not known, however, whether the same principles apply to declarative memory systems, such as those supporting semantic learning. Here, we demonstrate with fMRI that the brain parametrically encodes the degree to which new factual information violates expectations based on prior knowledge and beliefs-most prominently in the ventral striatum, and cortical regions supporting declarative memory encoding. These semantic prediction errors determine the extent to which information is incorporated into long-term memory, such that learning is superior when incoming information counters strong incorrect recollections, thereby eliciting large prediction errors. Paradoxically, by the same account, strong accurate recollections are more amenable to being supplanted by misinformation, engendering false memories. These findings highlight a commonality in brain mechanisms and computational rules that govern declarative and nondeclarative learning, traditionally deemed dissociable.

The anterior-ventrolateral temporal lobe contributes to boosting visual working memory capacity for items carrying semantic information.

PubMed

Chiou, Rocco; Lambon Ralph, Matthew A

2018-04-01

Working memory (WM) is a buffer that temporarily maintains information, be it visual or auditory, in an active state, caching its contents for online rehearsal or manipulation. How the brain enables long-term semantic knowledge to affect the WM buffer is a theoretically significant issue awaiting further investigation. In the present study, we capitalise on the knowledge about famous individuals as a 'test-case' to study how it impinges upon WM capacity for human faces and its neural substrate. Using continuous theta-burst transcranial stimulation combined with a psychophysical task probing WM storage for varying contents, we provide compelling evidence that (1) faces (regardless of familiarity) continued to accrue in the WM buffer with longer encoding time, whereas for meaningless stimuli (colour shades) there was little increment; (2) the rate of WM accrual was significantly more efficient for famous faces, compared to unknown faces; (3) the right anterior-ventrolateral temporal lobe (ATL) causally mediated this superior WM storage for famous faces. Specifically, disrupting the ATL (a region tuned to semantic knowledge including person identity) selectively hinders WM accrual for celebrity faces while leaving the accrual for unfamiliar faces intact. Further, this 'semantically-accelerated' storage is impervious to disruption of the right middle frontal gyrus and vertex, supporting the specific and causative contribution of the right ATL. Our finding advances the understanding of the neural architecture of WM, demonstrating that it depends on interaction with long-term semantic knowledge underpinned by the ATL, which causally expands the WM buffer when visual content carries semantic information. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Long-term interference at the semantic level: Evidence from blocked-cyclic picture matching.

PubMed

Wei, Tao; Schnur, Tatiana T

2016-01-01

Processing semantically related stimuli creates interference across various domains of cognition, including language and memory. In this study, we identify the locus and mechanism of interference when retrieving meanings associated with words and pictures. Subjects matched a probe stimulus (e.g., cat) to its associated target picture (e.g., yarn) from an array of unrelated pictures. Across trials, probes were either semantically related or unrelated. To test the locus of interference, we presented probes as either words or pictures. If semantic interference occurs at the stage common to both tasks, that is, access to semantic representations, then interference should occur in both probe presentation modalities. Results showed clear semantic interference effects independent of presentation modality and lexical frequency, confirming a semantic locus of interference in comprehension. To test the mechanism of interference, we repeated trials across 4 presentation cycles and manipulated the number of unrelated intervening trials (zero vs. two). We found that semantic interference was additive across cycles and survived 2 intervening trials, demonstrating interference to be long-lasting as opposed to short-lived. However, interference was smaller with zero versus 2 intervening trials, which we interpret to suggest that short-lived facilitation counteracted the long-lived interference. We propose that retrieving meanings associated with words/pictures from the same semantic category yields both interference due to long-lasting changes in connection strength between semantic representations (i.e., incremental learning) and facilitation caused by short-lived residual activation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Temporal information processing in short- and long-term memory of patients with schizophrenia.

PubMed

Landgraf, Steffen; Steingen, Joerg; Eppert, Yvonne; Niedermeyer, Ulrich; van der Meer, Elke; Krueger, Frank

2011-01-01

Cognitive deficits of patients with schizophrenia have been largely recognized as core symptoms of the disorder. One neglected factor that contributes to these deficits is the comprehension of time. In the present study, we assessed temporal information processing and manipulation from short- and long-term memory in 34 patients with chronic schizophrenia and 34 matched healthy controls. On the short-term memory temporal-order reconstruction task, an incidental or intentional learning strategy was deployed. Patients showed worse overall performance than healthy controls. The intentional learning strategy led to dissociable performance improvement in both groups. Whereas healthy controls improved on a performance measure (serial organization), patients improved on an error measure (inappropriate semantic clustering) when using the intentional instead of the incidental learning strategy. On the long-term memory script-generation task, routine and non-routine events of everyday activities (e.g., buying groceries) had to be generated in either chronological or inverted temporal order. Patients were slower than controls at generating events in the chronological routine condition only. They also committed more sequencing and boundary errors in the inverted conditions. The number of irrelevant events was higher in patients in the chronological, non-routine condition. These results suggest that patients with schizophrenia imprecisely access temporal information from short- and long-term memory. In short-term memory, processing of temporal information led to a reduction in errors rather than, as was the case in healthy controls, to an improvement in temporal-order recall. When accessing temporal information from long-term memory, patients were slower and committed more sequencing, boundary, and intrusion errors. Together, these results suggest that time information can be accessed and processed only imprecisely by patients who provide evidence for impaired time comprehension. This could contribute to symptomatic cognitive deficits and strategic inefficiency in schizophrenia.

Brain oscillatory subsequent memory effects differ in power and long-range synchronization between semantic and survival processing.

PubMed

Fellner, Marie-Christin; Bäuml, Karl-Heinz T; Hanslmayr, Simon

2013-10-01

Memory crucially depends on the way information is processed during encoding. Differences in processes during encoding not only lead to differences in memory performance but also rely on different brain networks. Although these assumptions are corroborated by several previous fMRI and ERP studies, little is known about how brain oscillations dissociate between different memory encoding tasks. The present study therefore compared encoding related brain oscillatory activity elicited by two very efficient encoding tasks: a typical deep semantic item feature judgment task and a more elaborative survival encoding task. Subjects were asked to judge words either for survival relevance or for animacy, as indicated by a cue presented prior to the item. This allowed dissociating pre-item activity from item-related activity for both tasks. Replicating prior studies, survival processing led to higher recognition performance than semantic processing. Successful encoding in the semantic condition was reflected by a strong decrease in alpha and beta power, whereas successful encoding in the survival condition was related to increased alpha and beta long-range phase synchrony. Moreover, a pre-item subsequent memory effect in theta power was found which did not vary with encoding condition. These results show that measures of local synchrony (power) and global long range-synchrony (phase synchronization) dissociate between memory encoding processes. Whereas semantic encoding was reflected in decreases in local synchrony, increases in global long range synchrony were related to elaborative survival encoding, presumably reflecting the involvement of a more widespread cortical network in this task. Copyright © 2013 Elsevier Inc. All rights reserved.

Event-Based Prospective Memory Is Independently Associated with Self-Report of Medication Management in Older Adults

PubMed Central

Woods, Steven Paul; Weinborn, Michael; Maxwell, Brenton R.; Gummery, Alice; Mo, Kevin; Ng, Amanda R. J.; Bucks, Romola S.

2014-01-01

Background Identifying potentially modifiable risk factors for medication non-adherence in older adults is important in order to enhance screening and intervention efforts designed to improve medication-taking behavior and health outcomes. The current study sought to determine the unique contribution of prospective memory (i.e., “remembering to remember”) to successful self-reported medication management in older adults. Methods Sixty-five older adults with current medication prescriptions completed a comprehensive research evaluation of sociodemographic, psychiatric, and neurocognitive functioning, which included the Memory for Adherence to Medication Scale (MAMS), Prospective and Retrospective Memory Questionnaire (PRMQ), and a performance-based measure of prospective memory that measured both semantically-related and semantically-unrelated cue-intention (i.e., when-what) pairings. Results A series of hierarchical regressions controlling for biopsychosocial, other neurocognitive, and medication-related factors showed that elevated complaints on the PM scale of the PRMQ and worse performance on an objective semantically-unrelated event-based prospective memory task were independent predictors of poorer medication adherence as measured by the MAMS. Conclusions Prospective memory plays an important role in self-report of successful medication management among older adults. Findings may have implications for screening for older individuals “at risk” of non-adherence, as well as the development of prospective memory-based interventions to improve medication adherence and, ultimately, long-term health outcomes in older adults. PMID:24410357

The neurobiology of the human memory.

PubMed

Fietta, Pierluigi; Fietta, Pieranna

2011-01-01

Memory can be defined as the ability to acquire, process, store, and retrieve information. Memory is indispensable for learning, adaptation, and survival of every living organism. In humans, the remembering process has acquired great flexibility and complexity, reaching close links with other mental functions, such as thinking and emotions. Changes in synaptic connectivity and interactions among multiple neural networks provide the neurobiological substrates for memory encoding, retention, and consolidation. Memory may be categorized as short-term and long-term memory (according to the storage temporal duration), as implicit and explicit memory (with respect to the consciousness of remembering), as declarative (knowing that [fact]) and procedural (knowing how [skill]) memory, or as sensory (echoic, iconic and haptil), semantic, and episodic memory (according to the various remembering domains). Significant advances have been obtained in understanding memory neurobiology, but much remains to be learned in its cognitive, psychological, and phenomenological aspects.

Functional segregation of the inferior frontal gyrus for syntactic processes: a functional magnetic-resonance imaging study.

PubMed

Uchiyama, Yuji; Toyoda, Hiroshi; Honda, Manabu; Yoshida, Haruyo; Kochiyama, Takanori; Ebe, Kazutoshi; Sadato, Norihiro

2008-07-01

We used functional magnetic resonance imaging in 18 normal volunteers to determine whether there is separate representation of syntactic, semantic, and verbal working memory processing in the left inferior frontal gyrus (GFi). We compared a sentence comprehension task with a short-term memory maintenance task to identify syntactic and semantic processing regions. To investigate the effects of syntactic and verbal working memory load while minimizing the differences in semantic processes, we used comprehension tasks with garden-path (GP) sentences, which require re-parsing, and non-garden-path (NGP) sentences. Compared with the short-term memory task, sentence comprehension activated the left GFi, including Brodmann areas (BAs) 44, 45, and 47, and the left superior temporal gyrus. In GP versus NGP sentences, there was greater activity in the left BAs 44, 45, and 46 extending to the left anterior insula, the pre-supplementary motor area, and the right cerebellum. In the left GFi, verbal working memory activity was located more dorsally (BA 44/45), semantic processing was located more ventrally (BA 47), and syntactic processing was located in between (BA 45). These findings indicate a close relationship between semantic and syntactic processes, and suggest that BA 45 might link verbal working memory and semantic processing via syntactic unification processes.

Reinforcement Learning and Episodic Memory in Humans and Animals: An Integrative Framework.

PubMed

Gershman, Samuel J; Daw, Nathaniel D

2017-01-03

We review the psychology and neuroscience of reinforcement learning (RL), which has experienced significant progress in the past two decades, enabled by the comprehensive experimental study of simple learning and decision-making tasks. However, one challenge in the study of RL is computational: The simplicity of these tasks ignores important aspects of reinforcement learning in the real world: (a) State spaces are high-dimensional, continuous, and partially observable; this implies that (b) data are relatively sparse and, indeed, precisely the same situation may never be encountered twice; furthermore, (c) rewards depend on the long-term consequences of actions in ways that violate the classical assumptions that make RL tractable. A seemingly distinct challenge is that, cognitively, theories of RL have largely involved procedural and semantic memory, the way in which knowledge about action values or world models extracted gradually from many experiences can drive choice. This focus on semantic memory leaves out many aspects of memory, such as episodic memory, related to the traces of individual events. We suggest that these two challenges are related. The computational challenge can be dealt with, in part, by endowing RL systems with episodic memory, allowing them to (a) efficiently approximate value functions over complex state spaces, (b) learn with very little data, and (c) bridge long-term dependencies between actions and rewards. We review the computational theory underlying this proposal and the empirical evidence to support it. Our proposal suggests that the ubiquitous and diverse roles of memory in RL may function as part of an integrated learning system.

Automatic semantic encoding in verbal short-term memory: evidence from the concreteness effect.

PubMed

Campoy, Guillermo; Castellà, Judit; Provencio, Violeta; Hitch, Graham J; Baddeley, Alan D

2015-01-01

The concreteness effect in verbal short-term memory (STM) tasks is assumed to be a consequence of semantic encoding in STM, with immediate recall of concrete words benefiting from richer semantic representations. We used the concreteness effect to test the hypothesis that semantic encoding in standard verbal STM tasks is a consequence of controlled, attention-demanding mechanisms of strategic semantic retrieval and encoding. Experiment 1 analysed the effect of presentation rate, with slow presentations being assumed to benefit strategic, time-dependent semantic encoding. Experiments 2 and 3 provided a more direct test of the strategic hypothesis by introducing three different concurrent attention-demanding tasks. Although Experiment 1 showed a larger concreteness effect with slow presentations, the following two experiments yielded strong evidence against the strategic hypothesis. Limiting available attention resources by concurrent tasks reduced global memory performance, but the concreteness effect was equivalent to that found in control conditions. We conclude that semantic effects in STM result from automatic semantic encoding and provide tentative explanations for the interaction between the concreteness effect and the presentation rate.

The effect of concurrent semantic categorization on delayed serial recall.

PubMed

Acheson, Daniel J; MacDonald, Maryellen C; Postle, Bradley R

2011-01-01

The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Participants engaged in 2 picture-judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content (concrete words in Experiment 1 and 3; nonwords in Experiments 2 and 3). Picture judgments varied in the extent to which they required accessing visual semantic information (i.e., semantic categorization and line orientation judgments). Results showed that, relative to line-orientation judgments, engaging in semantic categorization judgments increased the proportion of item-ordering errors for concrete lists but did not affect error proportions for nonword lists. Furthermore, although more ordering errors were observed for phonologically similar relative to dissimilar lists, no interactions were observed between the phonological overlap and picture-judgment task manipulations. These results demonstrate that lexical-semantic representations can affect the serial ordering of items in short-term memory. Furthermore, the dual-task paradigm provides a new method for examining when and how semantic representations affect memory performance.

The Effect of Concurrent Semantic Categorization on Delayed Serial Recall

PubMed Central

Acheson, Daniel J.; MacDonald, Maryellen C.; Postle, Bradley R.

2010-01-01

The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Subjects engaged in two picture judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content (concrete words in Experiment 1 and 3; nonwords in Experiments 2 and 3). Picture judgments varied in the extent to which they required accessing visual semantic information (i.e., semantic categorization and line orientation judgments). Results showed that, relative to line orientation judgments, engaging in semantic categorization judgments increased the proportion of item ordering errors for concrete lists but did not affect error proportions for nonword lists. Furthermore, although more ordering errors were observed for phonologically similar relative to dissimilar lists, no interactions were observed between the phonological overlap and picture judgment task manipulations. These results thus demonstrate that lexical-semantic representations can affect the serial ordering of items in short-term memory. Furthermore, the dual-task paradigm provides a new method for examining when and how semantic representations affect memory performance. PMID:21058880

How long-term memory and accentuation interact during spoken language comprehension.

PubMed

Li, Xiaoqing; Yang, Yufang

2013-04-01

Spoken language comprehension requires immediate integration of different information types, such as semantics, syntax, and prosody. Meanwhile, both the information derived from speech signals and the information retrieved from long-term memory exert their influence on language comprehension immediately. Using EEG (electroencephalogram), the present study investigated how the information retrieved from long-term memory interacts with accentuation during spoken language comprehension. Mini Chinese discourses were used as stimuli, with an interrogative or assertive context sentence preceding the target sentence. The target sentence included one critical word conveying new information. The critical word was either highly expected or lowly expected given the information retrieved from long-term memory. Moreover, the critical word was either consistently accented or inconsistently de-accented. The results revealed that for lowly expected new information, inconsistently de-accented words elicited a larger N400 and larger theta power increases (4-6 Hz) than consistently accented words. In contrast, for the highly expected new information, consistently accented words elicited a larger N400 and larger alpha power decreases (8-14 Hz) than inconsistently de-accented words. The results suggest that, during spoken language comprehension, the effect of accentuation interacted with the information retrieved from long-term memory immediately. Moreover, our results also have important consequences for our understanding of the processing nature of the N400. The N400 amplitude is not only enhanced for incorrect information (new and de-accented word) but also enhanced for correct information (new and accented words). Copyright © 2013 Elsevier Ltd. All rights reserved.

Long-lasting perceptual priming and semantic learning in amnesia: a case experiment.

PubMed

Tulving, E; Hayman, C A; Macdonald, C A

1991-07-01

An investigation of perceptual priming and semantic learning in the severely amnesic subject K.C. is reported. He was taught 64 three-word sentences and tested for his ability to produce the final word of each sentence. Despite a total lack of episodic memory, he exhibited (a) strong perceptual priming effects in word-fragment completion, which were retained essentially in full strength for 12 months, and (b) independent of perceptual priming, learning of new semantic facts, many of which were also retained for 12 months. K.C.'s semantic learning may be at least partly attributable to repeated study trials and minimal interference during learning. The findings suggest that perceptual priming and semantic learning are subserved by two memory systems different from episodic memory and that both systems (perceptual representation and semantic memory) are at least partially preserved in some amnesic subjects.

Long-Term Memory for Odors: Influences of Familiarity and Identification Across 64 Days

PubMed Central

Jönsson, Fredrik U.; Willander, Johan; Sikström, Sverker; Larsson, Maria

2015-01-01

Few studies have investigated long-term odor recognition memory, although some early observations suggested that the forgetting rate of olfactory representations is slower than for other sensory modalities. This study investigated recognition memory across 64 days for high and low familiar odors and faces. Memory was assessed in 83 young participants at 4 occasions; immediate, 4, 16, and 64 days after encoding. The results indicated significant forgetting for odors and faces across the 64 days. The forgetting functions for the 2 modalities were not fundamentally different. Moreover, high familiar odors and faces were better remembered than low familiar ones, indicating an important role of semantic knowledge on recognition proficiency for both modalities. Although odor recognition was significantly better than chance at the 64 days testing, memory for the low familiar odors was relatively poor. Also, the results indicated that odor identification consistency across sessions, irrespective of accuracy, was positively related to successful recognition. PMID:25740304

Strategic retrieval and the frontal lobes: evidence from confabulation and amnesia.

PubMed

Moscovitch, M; Melo, B

1997-07-01

Confabulation and amnesia are considered disorders of episodic but not of semantic memory. To test the limits of this view, retrieval from episodic and semantic memory was investigated in eight confabulating and nine non-confabulating amnesic subjects, and in 17 matched control subjects, by using a personal and an historical version of the Crovitz [Unconstrained search in long-term memory, Paper presented at the meeting of the Psychonomic Society, St Louis, MO, 1973] cue-word test. In response to cue words such as letter or battle subjects had to describe in detail, respectively, a related event from their personal lives or from history before their birth. We found that a subset of amnesic subjects, those with presumed damage or dysfunction in the region of the ventromedial frontal cortex, would confabulate in response to these cues. Their confabulations involved semantic, historical memories, as much as episodic, personal ones: and that distortions of content were at least as common as those of time. Even when not confabulating, they had much more difficulty than other amnesic subjects in recovering memories related to these cues. In confabulating, as compared to non-confabulating, amnesic subjects, prompting led to an increase in confabulations but also to greater recovery of veridical memories. By comparison, non-confabulating amnesic subjects whose memory loss was as severe as that of the confabulators, had a milder deficit on the personal as well as the historical cue-word test. They benefited from prompting somewhat more than matched control subjects. These results suggest that confabulation is associated with impaired strategic retrieval processes resulting from damage in the region of the ventromedial frontal cortex. These strategic retrieval processes help initiate and guide search in episodic and in semantic memory and they help monitor and organize the output from those systems.

Differences in Processing of Taxonomic and Sequential Relations in Semantic Memory: An fMRI Investigation

ERIC Educational Resources Information Center

Kuchinke, Lars; van der Meer, Elke; Krueger, Frank

2009-01-01

Conceptual knowledge of our world is represented in semantic memory in terms of concepts and semantic relations between concepts. We used functional magnetic resonance imaging (fMRI) to examine the cortical regions underlying the processing of sequential and taxonomic relations. Participants were presented verbal cues and performed three tasks:…

An Agent-Based Model for the Role of Short-Term Memory Enhancement in the Emergence of Grammatical Agreement.

PubMed

Vera, Javier

2018-01-01

What is the influence of short-term memory enhancement on the emergence of grammatical agreement systems in multi-agent language games? Agreement systems suppose that at least two words share some features with each other, such as gender, number, or case. Previous work, within the multi-agent language-game framework, has recently proposed models stressing the hypothesis that the emergence of a grammatical agreement system arises from the minimization of semantic ambiguity. On the other hand, neurobiological evidence argues for the hypothesis that language evolution has mainly related to an increasing of short-term memory capacity, which has allowed the online manipulation of words and meanings participating particularly in grammatical agreement systems. Here, the main aim is to propose a multi-agent language game for the emergence of a grammatical agreement system, under measurable long-range relations depending on the short-term memory capacity. Computer simulations, based on a parameter that measures the amount of short-term memory capacity, suggest that agreement marker systems arise in a population of agents equipped at least with a critical short-term memory capacity.

What does a patient with semantic dementia remember in verbal short-term memory? Order and sound but not words.

PubMed

Majerus, Steve; Norris, Dennis; Patterson, Karalyn

2007-03-01

In this study, we explored capacities for three different aspects of short-term verbal memory in patients with semantic dementia. As expected, the two patients had poor recall for lexico-semantic item information, as assessed by immediate serial recall of word lists. In contrast, their short-term memory for phonological information was preserved, as evidenced by normal performance for immediate serial recall of nonword lists, with normal or increased nonword phonotactic-frequency effects, and increased sensitivity to phonological lures in a delayed probe recognition task. Furthermore, the patients appeared to have excellent memory for the serial order of the words in a list. These data provide further support for the proposal that language knowledge is a major determining factor of verbal STM capacity, but they also highlight the necessary distinction of processes involved in item and order recall, as proposed by recent models of STM.

Semantic Memory Is Key to Binding Phonology: Converging Evidence from Immediate Serial Recall in Semantic Dementia and Healthy Participants

ERIC Educational Resources Information Center

Hoffman, Paul; Jefferies, Elizabeth; Ehsan, Sheeba; Jones, Roy W.; Lambon Ralph, Matthew A.

2009-01-01

Patients with semantic dementia (SD) make numerous phoneme migration errors when recalling lists of words they no longer fully understand, suggesting that word meaning makes a critical contribution to phoneme binding in verbal short-term memory. Healthy individuals make errors that appear similar when recalling lists of nonwords, which also lack…

A Developmental Study of Conceptual, Semantic Differential, and Acoustical Dimensions as Encoding Categories in Short-Term Memory. Final Report.

ERIC Educational Resources Information Center

Pender, Nola J.

The purpose of this research was to investigate developmental changes in encoding processes. It attempted to determine the extent to which children of varying ages utilize semantic (denotative or connotative) and acoustical encoding categories in a short-term memory task. It appears to be a reasonable assumption that as associational hierarchies…

A predictive framework for evaluating models of semantic organization in free recall

PubMed Central

Morton, Neal W; Polyn, Sean M.

2016-01-01

Research in free recall has demonstrated that semantic associations reliably influence the organization of search through episodic memory. However, the specific structure of these associations and the mechanisms by which they influence memory search remain unclear. We introduce a likelihood-based model-comparison technique, which embeds a model of semantic structure within the context maintenance and retrieval (CMR) model of human memory search. Within this framework, model variants are evaluated in terms of their ability to predict the specific sequence in which items are recalled. We compare three models of semantic structure, latent semantic analysis (LSA), global vectors (GloVe), and word association spaces (WAS), and find that models using WAS have the greatest predictive power. Furthermore, we find evidence that semantic and temporal organization is driven by distinct item and context cues, rather than a single context cue. This finding provides important constraint for theories of memory search. PMID:28331243

Interactions between mood and the structure of semantic memory: event-related potentials evidence

PubMed Central

Pinheiro, Ana P.; del Re, Elisabetta; Nestor, Paul G; McCarley, Robert W.; Gonçalves, Óscar F.

2013-01-01

Recent evidence suggests that affect acts as modulator of cognitive processes and in particular that induced mood has an effect on the way semantic memory is used on-line. We used event-related potentials (ERPs) to examine affective modulation of semantic information processing under three different moods: neutral, positive and negative. Fifteen subjects read 324 pairs of sentences, after mood induction procedure with 30 pictures of neutral, 30 pictures of positive and 30 pictures of neutral valence: 108 sentences were read in each mood induction condition. Sentences ended with three word types: expected words, within-category violations, and between-category violations. N400 amplitude was measured to the three word types under each mood induction condition. Under neutral mood, a congruency (more negative N400 amplitude for unexpected relative to expected endings) and a category effect (more negative N400 amplitude for between- than to within-category violations) were observed. Also, results showed differences in N400 amplitude for both within- and between-category violations as a function of mood: while positive mood tended to facilitate the integration of unexpected but related items, negative mood made their integration as difficult as unexpected and unrelated items. These findings suggest the differential impact of mood on access to long-term semantic memory during sentence comprehension. PMID:22434931

Interactions between mood and the structure of semantic memory: event-related potentials evidence.

PubMed

Pinheiro, Ana P; del Re, Elisabetta; Nestor, Paul G; McCarley, Robert W; Gonçalves, Óscar F; Niznikiewicz, Margaret

2013-06-01

Recent evidence suggests that affect acts as modulator of cognitive processes and in particular that induced mood has an effect on the way semantic memory is used on-line. We used event-related potentials (ERPs) to examine affective modulation of semantic information processing under three different moods: neutral, positive and negative. Fifteen subjects read 324 pairs of sentences, after mood induction procedure with 30 pictures of neutral, 30 pictures of positive and 30 pictures of neutral valence: 108 sentences were read in each mood induction condition. Sentences ended with three word types: expected words, within-category violations, and between-category violations. N400 amplitude was measured to the three word types under each mood induction condition. Under neutral mood, a congruency (more negative N400 amplitude for unexpected relative to expected endings) and a category effect (more negative N400 amplitude for between- than to within-category violations) were observed. Also, results showed differences in N400 amplitude for both within- and between-category violations as a function of mood: while positive mood tended to facilitate the integration of unexpected but related items, negative mood made their integration as difficult as unexpected and unrelated items. These findings suggest the differential impact of mood on access to long-term semantic memory during sentence comprehension.

When does word meaning affect immediate serial recall in semantic dementia?

PubMed

Jefferies, Elizabeth; Jones, Roy; Bateman, David; Ralph, Matthew A Lambon

2004-03-01

Patients with semantic dementia can show superior immediate recall of words that they still understand relatively well, as compared with more semantically degraded words, suggesting that conceptual knowledge makes a major contribution to phonological short-term memory. However, a number of studies have failed to show such a recall difference, challenging this view. We examined the effect of several methodological factors on the recall of known and degraded words in 4 patients with semantic dementia, in order to investigate possible reasons for this discrepancy. In general, our patients did exhibit poorer recall of the degraded words and made more phonological errors on these items. In addition, set size affected the magnitude of the recall advantage for known words. This finding suggests that semantic degradation influenced the rate of learning in the immediate recall task when the same items were presented repeatedly. The methods used to select known and degraded items also impacted on the recall difference. List length, however, did not affect the advantage for known words. The coherence of items in phonological short-term memory was affected by their semantic status, but not by the length of the material to be retained. The implications of these findings for the role of semantic and phonological representations in verbal short-term memory are discussed.

Semantic dementia Brazilian study of nineteen cases

PubMed Central

Senaha, Mirna Lie Hosogi; Caramelli, Paulo; Porto, Claudia Sellitto; Nitrini, Ricardo

2007-01-01

The term semantic dementia was devised by Snowden et al. in 1989 and nowadays, the semantic dementia syndrome is recognized as one of the clinical forms of frontotemporal lobar degeneration (FTLD) and is characterized by a language semantic disturbance associated to non-verbal semantic memory impairment. Objectives The aim of this study was to describe a Brazilian sample of 19 semantic dementia cases, emphasizing the clinical characteristics important for differential diagnosis of this syndrome. Methods Nineteen cases with semantic dementia were evaluated between 1999 and 2007. All patients were submitted to neurological evaluation, neuroimaging exams and cognitive, language and semantic memory evaluation. Results All patients presented fluent spontaneous speech, preservation of syntactic and phonological aspects of the language, word-finding difficulty, semantic paraphasias, word comprehension impairment, low performance in visual confrontation naming tasks, impairment on tests of non-verbal semantic memory and preservation of autobiographical memory and visuospatial skills. Regarding radiological investigations, temporal lobe atrophy and/or hypoperfusion were found in all patients. Conclusions The cognitive, linguistic and of neuroimaging data in our case series corroborate other studies showing that semantic dementia constitutes a syndrome with well defined clinical characteristics associated to temporal lobe atrophy. PMID:29213413

The relationships between memory systems and sleep stages.

PubMed

Rauchs, Géraldine; Desgranges, Béatrice; Foret, Jean; Eustache, Francis

2005-06-01

Sleep function remains elusive despite our rapidly increasing comprehension of the processes generating and maintaining the different sleep stages. Several lines of evidence support the hypothesis that sleep is involved in the off-line reprocessing of recently-acquired memories. In this review, we summarize the main results obtained in the field of sleep and memory consolidation in both animals and humans, and try to connect sleep stages with the different memory systems. To this end, we have collated data obtained using several methodological approaches, including electrophysiological recordings of neuronal ensembles, post-training modifications of sleep architecture, sleep deprivation and functional neuroimaging studies. Broadly speaking, all the various studies emphasize the fact that the four long-term memory systems (procedural memory, perceptual representation system, semantic and episodic memory, according to Tulving's SPI model; Tulving, 1995) benefit either from non-rapid eye movement (NREM) (not just SWS) or rapid eye movement (REM) sleep, or from both sleep stages. Tulving's classification of memory systems appears more pertinent than the declarative/non-declarative dichotomy when it comes to understanding the role of sleep in memory. Indeed, this model allows us to resolve several contradictions, notably the fact that episodic and semantic memory (the two memory systems encompassed in declarative memory) appear to rely on different sleep stages. Likewise, this model provides an explanation for why the acquisition of various types of skills (perceptual-motor, sensory-perceptual and cognitive skills) and priming effects, subserved by different brain structures but all designated by the generic term of implicit or non-declarative memory, may not benefit from the same sleep stages.

The Influence of Science Knowledge Structures on Children's Success in Solving Academic Problems.

ERIC Educational Resources Information Center

Champagne, Audrey B.; And Others

Presented is a study of eighth-grade students' academic problem-solving ability based on their knowledge structures, or their information stored in semantic or long-term memory. The authors describe a technique that they developed to probe knowledge structures with an extension of the card-sort method. The method, known as the Concept Structure…

Generalized dissociative amnesia: episodic, semantic and procedural memories lost and found.

PubMed

van der Hart, O; Nijenhuis, E

2001-10-01

This review tests Ribot's classic twofold categorization of generalized amnesia (GA) into Type I, total loss of episodic memory, and Type II, additional more or less extensive loss of semantic and/or procedural memory. It also explores his law of regression, according to which, cast in modern terms, recovery of lost procedural and semantic memories precedes recovery of episodic memory, as well as reported aetiological factors. Clinically and formally assessed cases of GA, published since 1845, were surveyed and further analysed. Over and above authentic episodic memory loss, cases differed widely in the extent of impairment of semantic and procedural memory. Recovery of semantic and procedural memory often preceded recovery of episodic memory. This particularly applied to authenticated trauma memories. To an extent, lost memories affected current functioning, and in some cases were associated with alternating dissociative personalities. Severe memory distortions upon memory recovery were not reported. Most cases were trauma or stress related, while in some cases the aetiology remained unknown. Contrary to the view expressed in DSM-IV, which states that dissociative amnesia pertains to an inability to recall personal information, GA may also involve loss and recovery of semantic and procedural memories. Since the loss of various memory types in GA is dimensional rather than categorical, Ribot's typological distinction does not hold. Some of the reviewed cases suggest a trauma-related aetiology. Generalized amnesia of varying degrees of severity can involve delayed retrieval of trauma memories, as well as the loss and delayed retrieval of the premorbid personality.

Explaining semantic short-term memory deficits: Evidence for the critical role of semantic control

PubMed Central

Hoffman, Paul; Jefferies, Elizabeth; Lambon Ralph, Matthew A.

2011-01-01

Patients with apparently selective short-term memory (STM) deficits for semantic information have played an important role in developing multi-store theories of STM and challenge the idea that verbal STM is supported by maintaining activation in the language system. We propose that semantic STM deficits are not as selective as previously thought and can occur as a result of mild disruption to semantic control processes, i.e., mechanisms that bias semantic processing towards task-relevant aspects of knowledge and away from irrelevant information. We tested three semantic STM patients with tasks that tapped four aspects of semantic control: (i) resolving ambiguity between word meanings, (ii) sensitivity to cues, (iii) ignoring irrelevant information and (iv) detecting weak semantic associations. All were impaired in conditions requiring more semantic control, irrespective of the STM demands of the task, suggesting a mild, but task-general, deficit in regulating semantic knowledge. This mild deficit has a disproportionate effect on STM tasks because they have high intrinsic control demands: in STM tasks, control is required to keep information active when it is no longer available in the environment and to manage competition between items held in memory simultaneously. By re-interpreting the core deficit in semantic STM patients in this way, we are able to explain their apparently selective impairment without the need for a specialised STM store. Instead, we argue that semantic STM patients occupy the mildest end of spectrum of semantic control disorders. PMID:21195105

Long-term repetition priming and semantic interference in a lexical-semantic matching task: tapping the links between object names and colors.

PubMed

Lloyd-Jones, Toby J; Nakabayashi, Kazuyo

2014-01-01

Using a novel paradigm to engage the long-term mappings between object names and the prototypical colors for objects, we investigated the retrieval of object-color knowledge as indexed by long-term priming (the benefit in performance from a prior encounter with the same or a similar stimulus); a process about which little is known. We examined priming from object naming on a lexical-semantic matching task. In the matching task participants encountered a visually presented object name (Experiment 1) or object shape (Experiment 2) paired with either a color patch or color name. The pairings could either match whereby both were consistent with a familiar object (e.g., strawberry and red) or mismatch (strawberry and blue). We used the matching task to probe knowledge about familiar objects and their colors pre-activated during object naming. In particular, we examined whether the retrieval of object-color information was modality-specific and whether this influenced priming. Priming varied with the nature of the retrieval process: object-color priming arose for object names but not object shapes and beneficial effects of priming were observed for color patches whereas inhibitory priming arose with color names. These findings have implications for understanding how object knowledge is retrieved from memory and modified by learning.

Working Memory Is Partially Preserved during Sleep

PubMed Central

Daltrozzo, Jérôme; Claude, Léa; Tillmann, Barbara; Bastuji, Hélène; Perrin, Fabien

2012-01-01

Although several cognitive processes, including speech processing, have been studied during sleep, working memory (WM) has never been explored up to now. Our study assessed the capacity of WM by testing speech perception when the level of background noise and the sentential semantic length (SSL) (amount of semantic information required to perceive the incongruence of a sentence) were modulated. Speech perception was explored with the N400 component of the event-related potentials recorded to sentence final words (50% semantically congruent with the sentence, 50% semantically incongruent). During sleep stage 2 and paradoxical sleep: (1) without noise, a larger N400 was observed for (short and long SSL) sentences ending with a semantically incongruent word compared to a congruent word (i.e. an N400 effect); (2) with moderate noise, the N400 effect (observed at wake with short and long SSL sentences) was attenuated for long SSL sentences. Our results suggest that WM for linguistic information is partially preserved during sleep with a smaller capacity compared to wake. PMID:23236418

Working memory is partially preserved during sleep.

PubMed

Daltrozzo, Jérôme; Claude, Léa; Tillmann, Barbara; Bastuji, Hélène; Perrin, Fabien

2012-01-01

Although several cognitive processes, including speech processing, have been studied during sleep, working memory (WM) has never been explored up to now. Our study assessed the capacity of WM by testing speech perception when the level of background noise and the sentential semantic length (SSL) (amount of semantic information required to perceive the incongruence of a sentence) were modulated. Speech perception was explored with the N400 component of the event-related potentials recorded to sentence final words (50% semantically congruent with the sentence, 50% semantically incongruent). During sleep stage 2 and paradoxical sleep: (1) without noise, a larger N400 was observed for (short and long SSL) sentences ending with a semantically incongruent word compared to a congruent word (i.e. an N400 effect); (2) with moderate noise, the N400 effect (observed at wake with short and long SSL sentences) was attenuated for long SSL sentences. Our results suggest that WM for linguistic information is partially preserved during sleep with a smaller capacity compared to wake.

Semantic Cuing and the Scale Insensitivity of Recency and Contiguity

PubMed Central

Polyn, Sean M.; Erlikhman, Gennady; Kahana, Michael J.

2012-01-01

In recalling a set of previously experienced events, people exhibit striking effects of recency, contiguity, and similarity: Recent items tend to be recalled best and first, and items that were studied in neighboring positions or that are similar to one another in some other way tend to evoke one another during recall. Effects of recency and contiguity have most often been investigated in tasks that require people to recall random word lists. Similarity effects have most often been studied in tasks that require people to recall categorized word lists. Here we examine recency and contiguity effects in lists composed of items drawn from 3 distinct taxonomic categories and in which items from a given category are temporally separated from one another by items from other categories, all of which are tested for recall. We find evidence for long-term recency and for long-range contiguity, bolstering support for temporally sensitive models of memory and highlighting the importance of understanding the interaction between temporal and semantic information during memory search. PMID:21299330

Human ecstasy (MDMA) polydrug users have altered brain activation during semantic processing.

PubMed

Watkins, Tristan J; Raj, Vidya; Lee, Junghee; Dietrich, Mary S; Cao, Aize; Blackford, Jennifer U; Salomon, Ronald M; Park, Sohee; Benningfield, Margaret M; Di Iorio, Christina R; Cowan, Ronald L

2013-05-01

Ecstasy (3,4-methylenedioxymethamphetamine [MDMA]) polydrug users have verbal memory performance that is statistically significantly lower than that of control subjects. Studies have correlated long-term MDMA use with altered brain activation in regions that play a role in verbal memory. The aim of our study was to examine the association of lifetime ecstasy use with semantic memory performance and brain activation in ecstasy polydrug users. A total of 23 abstinent ecstasy polydrug users (age = 24.57 years) and 11 controls (age = 22.36 years) performed a two-part functional magnetic resonance imaging (fMRI) semantic encoding and recognition task. To isolate brain regions activated during each semantic task, we created statistical activation maps in which brain activation was greater for word stimuli than for non-word stimuli (corrected p < 0.05). During the encoding phase, ecstasy polydrug users had greater activation during semantic encoding bilaterally in language processing regions, including Brodmann areas 7, 39, and 40. Of this bilateral activation, signal intensity with a peak T in the right superior parietal lobe was correlated with lifetime ecstasy use (r s = 0.43, p = 0.042). Behavioral performance did not differ between groups. These findings demonstrate that ecstasy polydrug users have increased brain activation during semantic processing. This increase in brain activation in the absence of behavioral deficits suggests that ecstasy polydrug users have reduced cortical efficiency during semantic encoding, possibly secondary to MDMA-induced 5-HT neurotoxicity. Although pre-existing differences cannot be ruled out, this suggests the possibility of a compensatory mechanism allowing ecstasy polydrug users to perform equivalently to controls, providing additional support for an association of altered cerebral neurophysiology with MDMA exposure.

Human ecstasy (MDMA) polydrug users have altered brain activation during semantic processing

PubMed Central

Watkins, Tristan J.; Raj, Vidya; Lee, Junghee; Dietrich, Mary S.; Cao, Aize; Blackford, Jennifer U.; Salomon, Ronald M.; Park, Sohee; Benningfield, Margaret M.; Di Iorio, Christina R.; Cowan, Ronald L.

2012-01-01

Rationale Ecstasy (MDMA) polydrug users have verbal memory performance that is statistically significantly lower than comparison control subjects. Studies have correlated long-term MDMA use with altered brain activation in regions that play a role in verbal memory. Objectives The aim of our study was to examine the association of lifetime ecstasy use with semantic memory performance and brain activation in ecstasy polydrug users. Methods 23 abstinent ecstasy polydrug users (age=24.57) and 11 controls (age=22.36) performed a two-part fMRI semantic encoding and recognition task. To isolate brain regions activated during each semantic task, we created statistical activation maps in which brain activation was greater for word stimuli than for non-word stimuli (corrected p<0.05). Results During the encoding phase, ecstasy polydrug users had greater activation during semantic encoding bilaterally in language processing regions, including Brodmann Areas 7, 39, and 40. Of this bilateral activation, signal intensity with a peak T in the right superior parietal lobe was correlated with lifetime ecstasy use (rs=0.43, p=0.042). Behavioral performance did not differ between groups. Conclusions These findings demonstrate that ecstasy polydrug users have increased brain activation during semantic processing. This increase in brain activation in the absence of behavioral deficits suggests that ecstasy polydrug users have reduced cortical efficiency during semantic encoding, possibly secondary to MDMA-induced 5-HT neurotoxicity. Although pre-existing differences cannot be ruled out, this suggests the possibility of a compensatory mechanism allowing ecstasy polydrug users to perform equivalently to controls, providing additional support for an association of altered cerebral neurophysiology with MDMA exposure. PMID:23241648

Retrieval and Monitoring Processes during Visual Working Memory: An ERP Study of the Benefit of Visual Semantics

PubMed Central

Orme, Elizabeth; Brown, Louise A.; Riby, Leigh M.

2017-01-01

In this study, we examined electrophysiological indices of episodic remembering whilst participants recalled novel shapes, with and without semantic content, within a visual working memory paradigm. The components of interest were the parietal episodic (PE; 400–800 ms) and late posterior negativity (LPN; 500–900 ms), as these have previously been identified as reliable markers of recollection and post-retrieval monitoring, respectively. Fifteen young adults completed a visual matrix patterns task, assessing memory for low and high semantic visual representations. Matrices with either low semantic or high semantic content (containing familiar visual forms) were briefly presented to participants for study (1500 ms), followed by a retention interval (6000 ms) and finally a same/different recognition phase. The event-related potentials of interest were tracked from the onset of the recognition test stimuli. Analyses revealed equivalent amplitude for the earlier PE effect for the processing of both low and high semantic stimulus types. However, the LPN was more negative-going for the processing of the low semantic stimuli. These data are discussed in terms of relatively ‘pure’ and complete retrieval of high semantic items, where support can readily be recruited from semantic memory. However, for the low semantic items additional executive resources, as indexed by the LPN, are recruited when memory monitoring and uncertainty exist in order to recall previously studied items more effectively. PMID:28725203

Retrieval and Monitoring Processes during Visual Working Memory: An ERP Study of the Benefit of Visual Semantics.

PubMed

Orme, Elizabeth; Brown, Louise A; Riby, Leigh M

2017-01-01

In this study, we examined electrophysiological indices of episodic remembering whilst participants recalled novel shapes, with and without semantic content, within a visual working memory paradigm. The components of interest were the parietal episodic (PE; 400-800 ms) and late posterior negativity (LPN; 500-900 ms), as these have previously been identified as reliable markers of recollection and post-retrieval monitoring, respectively. Fifteen young adults completed a visual matrix patterns task, assessing memory for low and high semantic visual representations. Matrices with either low semantic or high semantic content (containing familiar visual forms) were briefly presented to participants for study (1500 ms), followed by a retention interval (6000 ms) and finally a same/different recognition phase. The event-related potentials of interest were tracked from the onset of the recognition test stimuli. Analyses revealed equivalent amplitude for the earlier PE effect for the processing of both low and high semantic stimulus types. However, the LPN was more negative-going for the processing of the low semantic stimuli. These data are discussed in terms of relatively 'pure' and complete retrieval of high semantic items, where support can readily be recruited from semantic memory. However, for the low semantic items additional executive resources, as indexed by the LPN, are recruited when memory monitoring and uncertainty exist in order to recall previously studied items more effectively.

The transience and nature of cognitive impairments in transient global amnesia: a meta-analysis.

PubMed

Jäger, Theodor; Bäzner, Hansjörg; Kliegel, Matthias; Szabo, Kristina; Hennerici, Michael G

2009-01-01

Transient global amnesia (TGA) is a clinical syndrome characterized by the sudden onset of severe amnesia without concomitant focal neurological symptoms. This meta-analysis of the cognitive characteristics of TGA addressed two main issues. First, we examined the hypothesis that the acute phase of TGA is associated with changes of anterograde and retrograde episodic long-term memory sparing semantic and short-term memory, while we had no clear prediction for potential reductions of executive functions due to the relative lack of previous studies addressing this issue. Second, we analyzed the time-course of changes in cognitive functions throughout three time intervals--acute (0-24 hours after TGA onset), postacute (24 hours to 5 days), and long-term phase (5-30 days)--to reveal whether there is a fast versus a delayed recovery. The results of the meta-analysis on 152 effect sizes from 25 studies showed that TGA is characterized by an extraordinarily large reduction of anterograde (d* = 1.89) and a somewhat milder reduction of retrograde (d* = 1.28) episodic long-term memory. Moreover, our results indicate the existence of additional, nonamnestic cognitive changes during TGA, because executive functions were also diminished (d* = 0.79). Reductions in both anterograde episodic long-term memory and executive function recover slowly, as slightly poorer performance in these cognitive domains can be found in the postacute phase (d*s = 0.32 and 0.44). All cognitive diminutions resolved within the long-term phase, by this calling into question previous reports of poorer performance of TGA patients relative to comparison subjects weeks or months after the attack.

Oscillatory mechanisms of process binding in memory.

PubMed

Klimesch, Wolfgang; Freunberger, Roman; Sauseng, Paul

2010-06-01

A central topic in cognitive neuroscience is the question, which processes underlie large scale communication within and between different neural networks. The basic assumption is that oscillatory phase synchronization plays an important role for process binding--the transient linking of different cognitive processes--which may be considered a special type of large scale communication. We investigate this question for memory processes on the basis of different types of oscillatory synchronization mechanisms. The reviewed findings suggest that theta and alpha phase coupling (and phase reorganization) reflect control processes in two large memory systems, a working memory and a complex knowledge system that comprises semantic long-term memory. It is suggested that alpha phase synchronization may be interpreted in terms of processes that coordinate top-down control (a process guided by expectancy to focus on relevant search areas) and access to memory traces (a process leading to the activation of a memory trace). An analogous interpretation is suggested for theta oscillations and the controlled access to episodic memories. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

A category-specific advantage for numbers in verbal short-term memory: evidence from semantic dementia.

PubMed

Jefferies, Elizabeth; Patterson, Karalyn; Jones, Roy W; Bateman, David; Lambon Ralph, Matthew A

2004-01-01

This study explored possible reasons for the striking difference between digit span and word span in patients with semantic dementia. Immediate serial recall (ISR) of number and non-number words was examined in four patients. For every case, the recall of single-digit numbers was normal whereas the recall of non-number words was impaired relative to controls. This difference extended to multi-digit numbers, and remained even when frequency, imageability, word length, set size and size of semantic category were matched for the numbers and words. The advantage for number words also applied to the patients' reading performance. Previous studies have suggested that semantic memory plays a critical role in verbal short-term memory (STM) and reading: patients with semantic dementia show superior recall and reading of words that are still relatively well known compared to previously known but now semantically degraded words. Additional assessments suggested that this semantic locus was the basis of the patients' category-specific advantage for numbers. Comprehension was considerably better for number than non-number words. Number knowledge may be relatively preserved in semantic dementia because the cortical atrophy underlying the condition typically spares the areas of the parietal lobes thought to be crucial in numerical cognition but involves the inferolateral temporal-lobes known to support general conceptual knowledge.

Lower cognitive performance among long-term type 1 diabetes survivors: A case-control study.

PubMed

Awad, Anna; Lundqvist, Robert; Rolandsson, Olov; Sundström, Anna; Eliasson, Mats

2017-08-01

Patients with type 1 diabetes (T1D) have an increased risk of cognitive dysfunction. The cognitive decrement is believed to depend on macro- and microvascular complications and long disease duration. Some patients do not develop these complications, but still report cognitive symptoms. We examined if long-standing T1D without complications is associated with lower cognitive performance. A group of patients (n=43) with long-standing T1D (>30years) without micro- or macro vascular complications was compared with a non-diabetic control group (n=86) on six cognitive tests which probed episodic memory, semantic memory, episodic short-term memory, visual attention and psychomotor speed. Each patient was matched with two controls regarding age, gender and education. A linear mixed effect model was used to analyze the data. The mean age was 57years and mean duration was 41years. Patients with diabetes had lower diastolic blood pressure but BMI, waist circumference, systolic blood pressure and smoking did not differ between groups. Patients had lower results than non-diabetic controls in episodic short-term memory (p<0.001) and also lower values on a test that mirrors visual attention and psychomotor speed (p=0.019). Long-standing T1D was associated with lower cognitive performance, regardless of other diabetes-related complications. Copyright © 2017 Elsevier Inc. All rights reserved.

What factors underlie children's susceptibility to semantic and phonological false memories? investigating the roles of language skills and auditory short-term memory.

PubMed

McGeown, Sarah P; Gray, Eleanor A; Robinson, Jamey L; Dewhurst, Stephen A

2014-06-01

Two experiments investigated the cognitive skills that underlie children's susceptibility to semantic and phonological false memories in the Deese/Roediger-McDermott procedure (Deese, 1959; Roediger & McDermott, 1995). In Experiment 1, performance on the Verbal Similarities subtest of the British Ability Scales (BAS) II (Elliott, Smith, & McCulloch, 1997) predicted correct and false recall of semantic lures. In Experiment 2, performance on the Yopp-Singer Test of Phonemic Segmentation (Yopp, 1988) did not predict correct recall, but inversely predicted the false recall of phonological lures. Auditory short-term memory was a negative predictor of false recall in Experiment 1, but not in Experiment 2. The findings are discussed in terms of the formation of gist and verbatim traces as proposed by fuzzy trace theory (Reyna & Brainerd, 1998) and the increasing automaticity of associations as proposed by associative activation theory (Howe, Wimmer, Gagnon, & Plumpton, 2009). Copyright © 2014 Elsevier B.V. All rights reserved.

The relationship between semantic short-term memory and immediate serial recall of known and unknown words and nonwords: data from two Chinese individuals with aphasia.

PubMed

Wong, Winsy; Low, Sam-Po

2008-07-01

The present study investigated verbal recall of semantically preserved and degraded words and nonwords by taking into consideration the status of one's semantic short-term memory (STM). Two experiments were conducted on 2 Chinese individuals with aphasia. The first experiment showed that they had largely preserved phonological processing abilities accompanied by mild but comparable semantic processing deficits; however, their performance on STM tasks revealed a double dissociation. The second experiment found that the participant with more preserved semantic STM had better recall of known words and nonwords than of their unknown counterparts, whereas such effects were absent in the patient with severe semantic STM deficit. The results are compatible with models that assume separate phonological and semantic STM components, such as that of R. C. Martin, M. Lesch, and M. Bartha (1999). In addition, the distribution of error types was different from previous studies. This is discussed in terms of the methodology of the authors' experiments and current views regarding the nature of semantic STM and representations in the Chinese mental lexicon. (c) 2008 APA

Individual differences in children's memory and reading comprehension: an investigation of semantic and inhibitory deficits.

PubMed

Cain, Kate

2006-07-01

Three experiments compared the verbal memory skills of children with poor reading comprehension with that of same-age good comprehenders. The aims were to determine if semantic and/or inhibitory deficits explained comprehenders' problems on measures of verbal short-term memory and verbal working memory. In Experiment 1 there were no group differences on word- and number-based measures of short-term storage and no evidence that semantic knowledge mediated word recall. In Experiment 2 poor comprehenders were impaired on word- and number-based assessments of working memory, the greatest deficit found on the word-based task. Error analysis of both word-based tasks revealed that poor comprehenders were more likely to recall items that should have been inhibited than were good comprehenders. Experiment 3 extended this finding: Poor comprehenders were less able to inhibit information that was no longer relevant. Together, these findings suggest that individual differences in inhibitory processing influence the ability to regulate the contents of working memory, which may contribute to the differential memory performance of good and poor comprehenders.

Transient global amnesia: implicit/explicit memory dissociation and PET assessment of brain perfusion and oxygen metabolism in the acute stage.

PubMed

Eustache, F; Desgranges, B; Petit-Taboué, M C; de la Sayette, V; Piot, V; Sablé, C; Marchal, G; Baron, J C

1997-09-01

To assess explicit memory and two components of implicit memory--that is, perceptual-verbal skill learning and lexical-semantic priming effects--as well as resting cerebral blood flow (CBF) and oxygen metabolism (CMRO2) during the acute phase of transient global amnesia. In a 59 year old woman, whose amnestic episode fulfilled all current criteria for transient global amnesia, a neuropsychological protocol was administered, including word learning, story recall, categorical fluency, mirror reading, and word stem completion tasks. PET was performed using the (15)O steady state inhalation method, while the patient still exhibited severe anterograde amnesia and was interleaved with the cognitive tests. There was a clear cut dissociation between impaired long term episodic memory and preserved implicit memory for its two components. Categorical fluency was significantly altered, suggesting word retrieval strategy--rather than semantic memory--impairment. The PET study disclosed a reduced CMRO2 with relatively or fully preserved CBF in the left prefrontotemporal cortex and lentiform nucleus, and the reverse pattern over the left occipital cortex. The PET alterations with patchy CBF-CMRO2 uncoupling would be compatible with a migraine-like phenomenon and indicate that the isolated assessment of perfusion in transient global amnesia may be misleading. The pattern of metabolic depression, with sparing of the hippocampal area, is one among the distinct patterns of brain dysfunction that underlie the (apparently) uniform clinical presentation of transient global amnesia. The finding of a left prefrontal hypometabolism in the face of impaired episodic memory and altered verbal fluency would fit present day concepts from PET activation studies about the role of this area in episodic and semantic memory encoding/retrieval. Likewise, the changes affecting the lenticular nucleus but sparing the caudate would be consistent with the normal performance in perceptual-verbal skill learning. Finally, unaltered lexical-semantic priming effects, despite left temporal cortex hypometabolism, suggest that these processes are subserved by a more distributed neocortical network.

Short-term Action Intentions Overrule Long-Term Semantic Knowledge

ERIC Educational Resources Information Center

van Elk, M.; van Schie, H.T.; Bekkering, H.

2009-01-01

In the present study, we investigated whether the preparation of an unusual action with an object (e.g. bringing a cup towards the eye) could selectively overrule long-term semantic representations. In the first experiment it was found that unusual action intentions activated short-term semantic goal representations, rather than long-term…

Phonological, visual, and semantic coding strategies and children's short-term picture memory span.

PubMed

Henry, Lucy A; Messer, David; Luger-Klein, Scarlett; Crane, Laura

2012-01-01

Three experiments addressed controversies in the previous literature on the development of phonological and other forms of short-term memory coding in children, using assessments of picture memory span that ruled out potentially confounding effects of verbal input and output. Picture materials were varied in terms of phonological similarity, visual similarity, semantic similarity, and word length. Older children (6/8-year-olds), but not younger children (4/5-year-olds), demonstrated robust and consistent phonological similarity and word length effects, indicating that they were using phonological coding strategies. This confirmed findings initially reported by Conrad (1971), but subsequently questioned by other authors. However, in contrast to some previous research, little evidence was found for a distinct visual coding stage at 4 years, casting doubt on assumptions that this is a developmental stage that consistently precedes phonological coding. There was some evidence for a dual visual and phonological coding stage prior to exclusive use of phonological coding at around 5-6 years. Evidence for semantic similarity effects was limited, suggesting that semantic coding is not a key method by which young children recall lists of pictures.

Discriminant cognitive factors in responder and non-responder patients with schizophrenia.

PubMed

Stip, E; Lussier, I; Ngan, E; Mendrek, A; Liddle, P

1999-12-01

To identify which improvements in cognitive function are associated with symptom resolution in schizophrenic patients treated with atypical antipsychotics. a prospective open trial with atypical neuroleptics (risperidone, clozapine, quetiapine). Inpatient and outpatient units, Institute of Psychiatry. Thirty-nine patients with schizophrenia according to DSM-IV criteria were included. Clinical and cognitive assessment were done at baseline (T0) and again after six months of treatment (T2). Twenty-five patients completed the trial. New-generation antipsychotics during six months. Patients were considered as responders if their PANSS score decreased at least 20% (n = 15) and non-responders if it did not (n = 10). a computerized cognitive assessment comprised tests of short-term-memory (digit span), explicit long-term memory (word pair learning), divided attention, selective attention and verbal fluency (orthographic and semantic). Clinical assessment included PANSS and ESRS. A discriminant function analysis was performed to determine which changes in cognitive performance predicted symptomatic response status. Semantic fluency and orthographic fluency were significant predictors. Together they correctly predicted responder status in 88% of cases. Memory was not a significant predictor of symptomatic response. Verbal fluency discriminated the responder from the non-responder group during a pharmacological treatment.

Long-term repetition priming and semantic interference in a lexical-semantic matching task: tapping the links between object names and colors

PubMed Central

Lloyd-Jones, Toby J.; Nakabayashi, Kazuyo

2014-01-01

Using a novel paradigm to engage the long-term mappings between object names and the prototypical colors for objects, we investigated the retrieval of object-color knowledge as indexed by long-term priming (the benefit in performance from a prior encounter with the same or a similar stimulus); a process about which little is known. We examined priming from object naming on a lexical-semantic matching task. In the matching task participants encountered a visually presented object name (Experiment 1) or object shape (Experiment 2) paired with either a color patch or color name. The pairings could either match whereby both were consistent with a familiar object (e.g., strawberry and red) or mismatch (strawberry and blue). We used the matching task to probe knowledge about familiar objects and their colors pre-activated during object naming. In particular, we examined whether the retrieval of object-color information was modality-specific and whether this influenced priming. Priming varied with the nature of the retrieval process: object-color priming arose for object names but not object shapes and beneficial effects of priming were observed for color patches whereas inhibitory priming arose with color names. These findings have implications for understanding how object knowledge is retrieved from memory and modified by learning. PMID:25009522

Confabulation in healthy aging is related to interference of overlearned, semantically similar information on episodic memory recall.

PubMed

Dalla Barba, Gianfranco; Attali, Eve; La Corte, Valentina

2010-07-01

Normal aging is characterized by reduced performance on tasks of long-term memory. Older adults (OA) not only show reduced performance on tasks of recall and recognition memory, but also, compared to young adults (YA), are more vulnerable to memory distortions. In this study we describe the performance of a group of OA and a group of YA on the recall of three different types of story: a previously unknown story, a well-known fairy tale (Sleeping Beauty), and a modified well-known fairy tale (Little Red Riding Hood is not eaten by the wolf). The aim of our study was to test the hypothesis that in OA strongly represented, overlearned information interferes with episodic recall-that is, the retrieval of specific, unique past episodes. OA produced significantly more confabulations than YA and in particular in the recall of the modified fairy tale. Our findings indicate that the interference of strongly represented, overlearned information in episodic memory recall is implicated in the production of confabulations in OA. This effect is particularly prominent when the to-be remembered episodic information shows strong semantic similarities with preexisting, overlearned information.

The Role of Shape in Semantic Memory Organization of Objects: An Experimental Study Using PI-Release.

PubMed

van Weelden, Lisanne; Schilperoord, Joost; Swerts, Marc; Pecher, Diane

2015-01-01

Visual information contributes fundamentally to the process of object categorization. The present study investigated whether the degree of activation of visual information in this process is dependent on the contextual relevance of this information. We used the Proactive Interference (PI-release) paradigm. In four experiments, we manipulated the information by which objects could be categorized and subsequently be retrieved from memory. The pattern of PI-release showed that if objects could be stored and retrieved both by (non-perceptual) semantic and (perceptual) shape information, then shape information was overruled by semantic information. If, however, semantic information could not be (satisfactorily) used to store and retrieve objects, then objects were stored in memory in terms of their shape. The latter effect was found to be strongest for objects from identical semantic categories.

Meeting an "impossible challenge" in semantic dementia: outstanding performance in numerical Sudoku and quantitative number knowledge.

PubMed

Papagno, Costanza; Semenza, Carlo; Girelli, Luisa

2013-11-01

This study describes a follow-up investigation of numerical abilities and visuospatial memory in a patient suffering from semantic dementia whose progressive decline of semantic memory variably affected different types of knowledge. Crucially, we investigated in detail her outstanding performance with Sudoku that has been only anecdotally reported in the previous literature. We tested spatial cognition and memory, body representation, number processing, calculation, and Sudoku tasks, and we compared the patient's performance with that of matched controls. In agreement with the neuroanatomical data, showing substantial sparing of the parietal lobes in the face of severe atrophy of the temporal (and frontal) regions, we report full preservation of skills known to be supported by intact parietal-basal ganglia networks, and impaired knowledge related to long-term stored declarative information mediated by temporal regions. Performance in tasks sensitive to parietal dysfunction (such as right-left orientation, finger gnosis, writing, and visuospatial memory) was normal; within the numerical domain, preserved quantity-based number knowledge dissociated from increasing difficulties with nonquantitative number knowledge (such as knowledge of encyclopedic and personal number facts) and arithmetic facts knowledge. This case confirms the relation between numbers and space, and, although indirectly, their anatomical correlates, underlining which abilities are preserved in the case of severe semantic loss. In addition, although Sudoku is not inherently numerical, the patient was able to solve even the most difficult pattern, provided that it required digits and not letters, showing that digits have, in any case, a specific status. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Non-Interfering Effects of Active Post-Encoding Tasks on Episodic Memory Consolidation in Humans

PubMed Central

Varma, Samarth; Takashima, Atsuko; Krewinkel, Sander; van Kooten, Maaike; Fu, Lily; Medendorp, W. Pieter; Kessels, Roy P. C.; Daselaar, Sander M.

2017-01-01

So far, studies that investigated interference effects of post-learning processes on episodic memory consolidation in humans have used tasks involving only complex and meaningful information. Such tasks require reallocation of general or encoding-specific resources away from consolidation-relevant activities. The possibility that interference can be elicited using a task that heavily taxes our limited brain resources, but has low semantic and hippocampal related long-term memory processing demands, has never been tested. We address this question by investigating whether consolidation could persist in parallel with an active, encoding-irrelevant, minimally semantic task, regardless of its high resource demands for cognitive processing. We distinguish the impact of such a task on consolidation based on whether it engages resources that are: (1) general/executive, or (2) specific/overlapping with the encoding modality. Our experiments compared subsequent memory performance across two post-encoding consolidation periods: quiet wakeful rest and a cognitively demanding n-Back task. Across six different experiments (total N = 176), we carefully manipulated the design of the n-Back task to target general or specific resources engaged in the ongoing consolidation process. In contrast to previous studies that employed interference tasks involving conceptual stimuli and complex processing demands, we did not find any differences between n-Back and rest conditions on memory performance at delayed test, using both recall and recognition tests. Our results indicate that: (1) quiet, wakeful rest is not a necessary prerequisite for episodic memory consolidation; and (2) post-encoding cognitive engagement does not interfere with memory consolidation when task-performance has minimal semantic and hippocampally-based episodic memory processing demands. We discuss our findings with reference to resource and reactivation-led interference theories. PMID:28424596

Non-Interfering Effects of Active Post-Encoding Tasks on Episodic Memory Consolidation in Humans.

PubMed

Varma, Samarth; Takashima, Atsuko; Krewinkel, Sander; van Kooten, Maaike; Fu, Lily; Medendorp, W Pieter; Kessels, Roy P C; Daselaar, Sander M

2017-01-01

So far, studies that investigated interference effects of post-learning processes on episodic memory consolidation in humans have used tasks involving only complex and meaningful information. Such tasks require reallocation of general or encoding-specific resources away from consolidation-relevant activities. The possibility that interference can be elicited using a task that heavily taxes our limited brain resources, but has low semantic and hippocampal related long-term memory processing demands, has never been tested. We address this question by investigating whether consolidation could persist in parallel with an active, encoding-irrelevant, minimally semantic task, regardless of its high resource demands for cognitive processing. We distinguish the impact of such a task on consolidation based on whether it engages resources that are: (1) general/executive, or (2) specific/overlapping with the encoding modality. Our experiments compared subsequent memory performance across two post-encoding consolidation periods: quiet wakeful rest and a cognitively demanding n-Back task. Across six different experiments (total N = 176), we carefully manipulated the design of the n-Back task to target general or specific resources engaged in the ongoing consolidation process. In contrast to previous studies that employed interference tasks involving conceptual stimuli and complex processing demands, we did not find any differences between n-Back and rest conditions on memory performance at delayed test, using both recall and recognition tests. Our results indicate that: (1) quiet, wakeful rest is not a necessary prerequisite for episodic memory consolidation; and (2) post-encoding cognitive engagement does not interfere with memory consolidation when task-performance has minimal semantic and hippocampally-based episodic memory processing demands. We discuss our findings with reference to resource and reactivation-led interference theories.

A Disorder of Executive Function and Its Role in Language Processing

PubMed Central

Martin, Randi C.; Allen, Corinne M.

2014-01-01

R. Martin and colleagues have proposed separate stores for the maintenance of phonological and semantic information in short-term memory. Evidence from patients with aphasia has shown that damage to these separable buffers has specific consequences for language comprehension and production, suggesting an interdependence between language and memory systems. This article discusses recent research on aphasic patients with limited-capacity short-term memories (STMs) and reviews evidence suggesting that deficits in retaining semantic information in STM may be caused by a disorder in the executive control process of inhibition, specific to verbal representations. In contrast, a phonological STM deficit may be due to overly rapid decay. In semantic STM deficits, it is hypothesized that the inhibitory deficit produces difficulty inhibiting irrelevant verbal representations, which may lead to excessive interference. In turn, the excessive interference associated with semantic STM deficits has implications for single-word and sentence processing, and it may be the source of the reduced STM capacity shown by these patients. PMID:18720317

The Role of Episodic and Semantic Memory in Episodic Foresight

ERIC Educational Resources Information Center

Martin-Ordas, Gema; Atance, Cristina M.; Louw, Alyssa

2012-01-01

In this paper we describe a special form of future thinking, termed "episodic foresight" and its relation with episodic and semantic memory. We outline the methodologies that have largely been developed in the last five years to assess this capacity in young children and non-human animals. Drawing on Tulving's definition of episodic and semantic…

The neural basis for novel semantic categorization.

PubMed

Koenig, Phyllis; Smith, Edward E; Glosser, Guila; DeVita, Chris; Moore, Peachie; McMillan, Corey; Gee, Jim; Grossman, Murray

2005-01-15

We monitored regional cerebral activity with BOLD fMRI during acquisition of a novel semantic category and subsequent categorization of test stimuli by a rule-based strategy or a similarity-based strategy. We observed different patterns of activation in direct comparisons of rule- and similarity-based categorization. During rule-based category acquisition, subjects recruited anterior cingulate, thalamic, and parietal regions to support selective attention to perceptual features, and left inferior frontal cortex to helps maintain rules in working memory. Subsequent rule-based categorization revealed anterior cingulate and parietal activation while judging stimuli whose conformity with the rules was readily apparent, and left inferior frontal recruitment during judgments of stimuli whose conformity was less apparent. By comparison, similarity-based category acquisition showed recruitment of anterior prefrontal and posterior cingulate regions, presumably to support successful retrieval of previously encountered exemplars from long-term memory, and bilateral temporal-parietal activation for perceptual feature integration. Subsequent similarity-based categorization revealed temporal-parietal, posterior cingulate, and anterior prefrontal activation. These findings suggest that large-scale networks support relatively distinct categorization processes during the acquisition and judgment of semantic category knowledge.

Semantic graphs and associative memories

NASA Astrophysics Data System (ADS)

Pomi, Andrés; Mizraji, Eduardo

2004-12-01

Graphs have been increasingly utilized in the characterization of complex networks from diverse origins, including different kinds of semantic networks. Human memories are associative and are known to support complex semantic nets; these nets are represented by graphs. However, it is not known how the brain can sustain these semantic graphs. The vision of cognitive brain activities, shown by modern functional imaging techniques, assigns renewed value to classical distributed associative memory models. Here we show that these neural network models, also known as correlation matrix memories, naturally support a graph representation of the stored semantic structure. We demonstrate that the adjacency matrix of this graph of associations is just the memory coded with the standard basis of the concept vector space, and that the spectrum of the graph is a code invariant of the memory. As long as the assumptions of the model remain valid this result provides a practical method to predict and modify the evolution of the cognitive dynamics. Also, it could provide us with a way to comprehend how individual brains that map the external reality, almost surely with different particular vector representations, are nevertheless able to communicate and share a common knowledge of the world. We finish presenting adaptive association graphs, an extension of the model that makes use of the tensor product, which provides a solution to the known problem of branching in semantic nets.

Does Controlling for Temporal Parameters Change the Levels-of-Processing Effect in Working Memory?

PubMed Central

Loaiza, Vanessa M.; Camos, Valérie

2016-01-01

The distinguishability between working memory (WM) and long-term memory has been a frequent and long-lasting source of debate in the literature. One recent method of identifying the relationship between the two systems has been to consider the influence of long-term memory effects, such as the levels-of-processing (LoP) effect, in WM. However, the few studies that have examined the LoP effect in WM have shown divergent results. This study examined the LoP effect in WM by considering a theoretically meaningful methodological aspect of the LoP span task. Specifically, we fixed the presentation duration of the processing component a priori because such fixed complex span tasks have shown differences when compared to unfixed tasks in terms of recall from WM as well as the latent structure of WM. After establishing a fixed presentation rate from a pilot study, the LoP span task presented memoranda in red or blue font that were immediately followed by two processing words that matched the memoranda in terms of font color or semantic relatedness. On presentation of the processing words, participants made deep or shallow processing decisions for each of the memoranda before a cue to recall them from WM. Participants also completed delayed recall of the memoranda. Results indicated that LoP affected delayed recall, but not immediate recall from WM. These results suggest that fixing temporal parameters of the LoP span task does not moderate the null LoP effect in WM, and further indicate that WM and long-term episodic memory are dissociable on the basis of LoP effects. PMID:27152126

Does Controlling for Temporal Parameters Change the Levels-of-Processing Effect in Working Memory?

PubMed

Loaiza, Vanessa M; Camos, Valérie

2016-01-01

The distinguishability between working memory (WM) and long-term memory has been a frequent and long-lasting source of debate in the literature. One recent method of identifying the relationship between the two systems has been to consider the influence of long-term memory effects, such as the levels-of-processing (LoP) effect, in WM. However, the few studies that have examined the LoP effect in WM have shown divergent results. This study examined the LoP effect in WM by considering a theoretically meaningful methodological aspect of the LoP span task. Specifically, we fixed the presentation duration of the processing component a priori because such fixed complex span tasks have shown differences when compared to unfixed tasks in terms of recall from WM as well as the latent structure of WM. After establishing a fixed presentation rate from a pilot study, the LoP span task presented memoranda in red or blue font that were immediately followed by two processing words that matched the memoranda in terms of font color or semantic relatedness. On presentation of the processing words, participants made deep or shallow processing decisions for each of the memoranda before a cue to recall them from WM. Participants also completed delayed recall of the memoranda. Results indicated that LoP affected delayed recall, but not immediate recall from WM. These results suggest that fixing temporal parameters of the LoP span task does not moderate the null LoP effect in WM, and further indicate that WM and long-term episodic memory are dissociable on the basis of LoP effects.

Categorizing words through semantic memory navigation

NASA Astrophysics Data System (ADS)

Borge-Holthoefer, J.; Arenas, A.

2010-03-01

Semantic memory is the cognitive system devoted to storage and retrieval of conceptual knowledge. Empirical data indicate that semantic memory is organized in a network structure. Everyday experience shows that word search and retrieval processes provide fluent and coherent speech, i.e. are efficient. This implies either that semantic memory encodes, besides thousands of words, different kind of links for different relationships (introducing greater complexity and storage costs), or that the structure evolves facilitating the differentiation between long-lasting semantic relations from incidental, phenomenological ones. Assuming the latter possibility, we explore a mechanism to disentangle the underlying semantic backbone which comprises conceptual structure (extraction of categorical relations between pairs of words), from the rest of information present in the structure. To this end, we first present and characterize an empirical data set modeled as a network, then we simulate a stochastic cognitive navigation on this topology. We schematize this latter process as uncorrelated random walks from node to node, which converge to a feature vectors network. By doing so we both introduce a novel mechanism for information retrieval, and point at the problem of category formation in close connection to linguistic and non-linguistic experience.

Modality specific semantic knowledge loss for unique items.

PubMed

Kartsounis, L D; Shallice, T

1996-03-01

We report the case of a man who, following a major myocardial infarction, suffered anoxia followed by significant event memory impairment. Investigations indicated that his semantic memory for word concepts and object meanings was well preserved. However, he had great difficulty in identifying in the visual (but not verbal) modality historically known people, such as Queen Elizabeth I and Napoleon, and well known world and London landmarks, such as the Parthenon and Buckingham Palace. This selective impairment could not be accounted for in terms of prosopagnosia or high level visual perceptual deficits and we interpret it as a modality specific semantic memory loss for unique objects.

Preexisting semantic representation improves working memory performance in the visuospatial domain.

PubMed

Rudner, Mary; Orfanidou, Eleni; Cardin, Velia; Capek, Cheryl M; Woll, Bencie; Rönnberg, Jerker

2016-05-01

Working memory (WM) for spoken language improves when the to-be-remembered items correspond to preexisting representations in long-term memory. We investigated whether this effect generalizes to the visuospatial domain by administering a visual n-back WM task to deaf signers and hearing signers, as well as to hearing nonsigners. Four different kinds of stimuli were presented: British Sign Language (BSL; familiar to the signers), Swedish Sign Language (SSL; unfamiliar), nonsigns, and nonlinguistic manual actions. The hearing signers performed better with BSL than with SSL, demonstrating a facilitatory effect of preexisting semantic representation. The deaf signers also performed better with BSL than with SSL, but only when WM load was high. No effect of preexisting phonological representation was detected. The deaf signers performed better than the hearing nonsigners with all sign-based materials, but this effect did not generalize to nonlinguistic manual actions. We argue that deaf signers, who are highly reliant on visual information for communication, develop expertise in processing sign-based items, even when those items do not have preexisting semantic or phonological representations. Preexisting semantic representation, however, enhances the quality of the gesture-based representations temporarily maintained in WM by this group, thereby releasing WM resources to deal with increased load. Hearing signers, on the other hand, may make strategic use of their speech-based representations for mnemonic purposes. The overall pattern of results is in line with flexible-resource models of WM.

Functional Magnetic Resonance Imaging of Semantic Memory as a Presymptomatic Biomarker of Alzheimer’s Disease Risk

PubMed Central

Sugarman, Michael A.; Woodard, John L.; Nielson, Kristy A.; Seidenberg, Michael; Smith, J. Carson; Durgerian, Sally; Rao, Stephen M.

2011-01-01

Extensive research efforts have been directed toward strategies for predicting risk of developing Alzheimer’s disease (AD) prior to the appearance of observable symptoms. Existing approaches for early detection of AD vary in terms of their efficacy, invasiveness, and ease of implementation. Several non-invasive magnetic resonance imaging strategies have been developed for predicting decline in cognitively healthy older adults. This review will survey a number of studies, beginning with the development of a famous name discrimination task used to identify neural regions that participate in semantic memory retrieval and to test predictions of several key theories of the role of the hippocampus in memory. This task has revealed medial temporal and neocortical contributions to recent and remote memory retrieval, and it has been used to demonstrate compensatory neural recruitment in older adults, apolipoprotein E ε4 carriers, and amnestic mild cognitive impairment patients. Recently, we have also found that the famous name discrimination task provides predictive value for forecasting episodic memory decline among asymptomatic older adults. Other studies investigating the predictive value of semantic memory tasks will also be presented. We suggest several advantages associated with the use of semantic processing tasks, particularly those based on person identification, in comparison to episodic memory tasks to study AD risk. Future directions for research and potential clinical uses of semantic memory paradigms are also discussed. PMID:21996618

Skilled memory in expert figure skaters.

PubMed

Deakin, J M; Allard, F

1991-01-01

The present studies extend skilled-memory theory to a domain involving the performance of motor sequences. Skilled figure skaters were better able than their less skilled counterparts to perform short skating sequences that were choreographed, rather than randomly constructed. Expert skaters encoded sequences for performance very differently from the way in which they encoded sequences that were verbally presented for verbal recall. Tasks interpolated between sequence and recall showed no significant influence on recall accuracy, implicating long-term memory in skating memory. There was little evidence for the use of retrieval structures when skaters learned the brief sequences used throughout these studies. Finally, expert skaters were able to judge the similarity of two skating elements faster than less skilled skaters, indicating a faster access to semantic memory for experts. The data indicate that skaters show many of the same skilled-memory characteristics as have been described in other skill domains involving memorization, such as digit span and memory for dinner orders.

Language and Short-Term Memory: The Role of Perceptual-Motor Affordance

PubMed Central

2014-01-01

The advantage for real words over nonwords in serial recall—the lexicality effect—is typically attributed to support for item-level phonology, either via redintegration, whereby partially degraded short-term traces are “cleaned up” via support from long-term representations of the phonological material or via the more robust temporary activation of long-term lexical phonological knowledge that derives from its combination with established lexical and semantic levels of representation. The much smaller effect of lexicality in serial recognition, where the items are re-presented in the recognition cue, is attributed either to the minimal role for redintegration from long-term memory or to the minimal role for item memory itself in such retrieval conditions. We show that the reduced lexicality effect in serial recognition is not a function of the retrieval conditions, but rather because previous demonstrations have used auditory presentation, and we demonstrate a robust lexicality effect for visual serial recognition in a setting where auditory presentation produces no such effect. Furthermore, this effect is abolished under conditions of articulatory suppression. We argue that linguistic knowledge affects the readiness with which verbal material is segmentally recoded via speech motor processes that support rehearsal and therefore affects tasks that involve recoding. On the other hand, auditory perceptual organization affords sequence matching in the absence of such a requirement for segmental recoding and therefore does not show such effects of linguistic knowledge. PMID:24797440

Language and short-term memory: the role of perceptual-motor affordance.

PubMed

Macken, Bill; Taylor, John C; Jones, Dylan M

2014-09-01

The advantage for real words over nonwords in serial recall--the lexicality effect--is typically attributed to support for item-level phonology, either via redintegration, whereby partially degraded short-term traces are "cleaned up" via support from long-term representations of the phonological material or via the more robust temporary activation of long-term lexical phonological knowledge that derives from its combination with established lexical and semantic levels of representation. The much smaller effect of lexicality in serial recognition, where the items are re-presented in the recognition cue, is attributed either to the minimal role for redintegration from long-term memory or to the minimal role for item memory itself in such retrieval conditions. We show that the reduced lexicality effect in serial recognition is not a function of the retrieval conditions, but rather because previous demonstrations have used auditory presentation, and we demonstrate a robust lexicality effect for visual serial recognition in a setting where auditory presentation produces no such effect. Furthermore, this effect is abolished under conditions of articulatory suppression. We argue that linguistic knowledge affects the readiness with which verbal material is segmentally recoded via speech motor processes that support rehearsal and therefore affects tasks that involve recoding. On the other hand, auditory perceptual organization affords sequence matching in the absence of such a requirement for segmental recoding and therefore does not show such effects of linguistic knowledge.

Proactive interference in a semantic short-term memory deficit: role of semantic and phonological relatedness.

PubMed

Hamilton, A Cris; Martin, Randi C

2007-01-01

Previous research has indicated that patients with semantic short-term memory (STM) deficits demonstrate unusual intrusions of previously presented material during serial recall tasks (Martin and Lesch, 1996). These intrusions suggest excessive proactive interference (PI) from previous lists. Here, we explore one such patient's susceptibility to PI. Experiment 1 demonstrated patient M.L.'s extreme susceptibility to PI using a probe recognition task that manipulates the recency of negative probes (the recent negatives task). When stimuli consisted of letters, M.L. showed greatly exaggerated effects of PI, well outside of the range of healthy control participants. Experiment 2 used a variation of the recent negatives task to examine the relative contribution of semantic and phonological relatedness in PI. This task manipulated semantic and phonological relatedness of probes and recently presented list items. Relative to healthy control participants, patient M.L. showed exaggerated interference effects for both phonological and semantically related probes, both for probes related to the current list and for probes related to the previous list. These data have important implications for theories of semantic STM deficits. Specifically, these data suggest that it is not the rapid decay of semantic representations that is responsible for difficulties in short-term recall, but rather the abnormal persistence of previously presented material. We propose that this susceptibility to PI is the result of a deficit in control processes acting on STM.

Deception and Cognitive Load: Expanding Our Horizon with a Working Memory Model

PubMed Central

Sporer, Siegfried L.

2016-01-01

Recently, studies on deception and its detection have increased dramatically. Many of these studies rely on the “cognitive load approach” as the sole explanatory principle to understand deception. These studies have been exclusively on lies about negative actions (usually lies of suspects of [mock] crimes). Instead, we need to re-focus more generally on the cognitive processes involved in generating both lies and truths, not just on manipulations of cognitive load. Using Baddeley’s (2000, 2007, 2012) working memory model, which integrates verbal and visual processes in working memory with retrieval from long-term memory and control of action, not only verbal content cues but also nonverbal, paraverbal, and linguistic cues can be investigated within a single framework. The proposed model considers long-term semantic, episodic and autobiographical memory and their connections with working memory and action. It also incorporates ironic processes of mental control (Wegner, 1994, 2009), the role of scripts and schemata and retrieval cues and retrieval processes. Specific predictions of the model are outlined and support from selective studies is presented. The model is applicable to different types of reports, particularly about lies and truths about complex events, and to different modes of production (oral, hand-written, typed). Predictions regarding several moderator variables and methods to investigate them are proposed. PMID:27092090

Deception and Cognitive Load: Expanding Our Horizon with a Working Memory Model.

PubMed

Sporer, Siegfried L

2016-01-01

Recently, studies on deception and its detection have increased dramatically. Many of these studies rely on the "cognitive load approach" as the sole explanatory principle to understand deception. These studies have been exclusively on lies about negative actions (usually lies of suspects of [mock] crimes). Instead, we need to re-focus more generally on the cognitive processes involved in generating both lies and truths, not just on manipulations of cognitive load. Using Baddeley's (2000, 2007, 2012) working memory model, which integrates verbal and visual processes in working memory with retrieval from long-term memory and control of action, not only verbal content cues but also nonverbal, paraverbal, and linguistic cues can be investigated within a single framework. The proposed model considers long-term semantic, episodic and autobiographical memory and their connections with working memory and action. It also incorporates ironic processes of mental control (Wegner, 1994, 2009), the role of scripts and schemata and retrieval cues and retrieval processes. Specific predictions of the model are outlined and support from selective studies is presented. The model is applicable to different types of reports, particularly about lies and truths about complex events, and to different modes of production (oral, hand-written, typed). Predictions regarding several moderator variables and methods to investigate them are proposed.

Memory illusion in high-functioning autism and Asperger's disorder.

PubMed

Kamio, Yoko; Toichi, Motomi

2007-05-01

In this study, 13 individuals with high-functioning autism (HFA), 15 individuals with Asperger's disorder (AD), and age-, and IQ-matched controls were presented a list of sentences auditorily. Participants then evaluated semantically related but new sentences and reported whether they were old or new. The total rates of false recognition for semantically related sentences were similar among the three groups. Nevertheless, memory illusion on some aspects was reduced in HFA participants. These results suggest that HFA have difficulties in semantic association. Although individuals with AD showed no quantitative abnormalities of memory illusion, some contributing factors were atypical. These findings are discussed in terms of schema theory, enhanced perceptual processing hypothesis, and weak central coherence hypothesis.

Benefits of deep encoding in Alzheimer disease. Analysis of performance on a memory task using the Item Specific Deficit Approach.

PubMed

Oltra-Cucarella, J; Pérez-Elvira, R; Duque, P

2014-06-01

the aim of this study is to test the encoding deficit hypothesis in Alzheimer disease (AD) using a recent method for correcting memory tests. To this end, a Spanish-language adaptation of the Free and Cued Selective Reminding Test was interpreted using the Item Specific Deficit Approach (ISDA), which provides three indices: Encoding Deficit Index, Consolidation Deficit Index, and Retrieval Deficit Index. We compared the performances of 15 patients with AD and 20 healthy control subjects and analysed results using either the task instructions or the ISDA approach. patients with AD displayed deficient encoding of more than half the information, but items that were encoded properly could be retrieved later with the help of the same semantic clues provided individually during encoding. Virtually all the information retained over the long-term was retrieved by using semantic clues. Encoding was shown to be the most impaired process, followed by retrieval and consolidation. Discriminant function analyses showed that ISDA indices are more sensitive and specific for detecting memory impairments in AD than are raw scores. These results indicate that patients with AD present impaired information encoding, but they benefit from semantic hints that help them recover previously learned information. This should be taken into account for intervention techniques focusing on memory impairments in AD. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

The Effect of Concurrent Semantic Categorization on Delayed Serial Recall

ERIC Educational Resources Information Center

Acheson, Daniel J.; MacDonald, Maryellen C.; Postle, Bradley R.

2011-01-01

The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Participants engaged in 2 picture-judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content…

Attending to auditory memory.

PubMed

Zimmermann, Jacqueline F; Moscovitch, Morris; Alain, Claude

2016-06-01

Attention to memory describes the process of attending to memory traces when the object is no longer present. It has been studied primarily for representations of visual stimuli with only few studies examining attention to sound object representations in short-term memory. Here, we review the interplay of attention and auditory memory with an emphasis on 1) attending to auditory memory in the absence of related external stimuli (i.e., reflective attention) and 2) effects of existing memory on guiding attention. Attention to auditory memory is discussed in the context of change deafness, and we argue that failures to detect changes in our auditory environments are most likely the result of a faulty comparison system of incoming and stored information. Also, objects are the primary building blocks of auditory attention, but attention can also be directed to individual features (e.g., pitch). We review short-term and long-term memory guided modulation of attention based on characteristic features, location, and/or semantic properties of auditory objects, and propose that auditory attention to memory pathways emerge after sensory memory. A neural model for auditory attention to memory is developed, which comprises two separate pathways in the parietal cortex, one involved in attention to higher-order features and the other involved in attention to sensory information. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2015 Elsevier B.V. All rights reserved.

Toward cognitive robotics

NASA Astrophysics Data System (ADS)

Laird, John E.

2009-05-01

Our long-term goal is to develop autonomous robotic systems that have the cognitive abilities of humans, including communication, coordination, adapting to novel situations, and learning through experience. Our approach rests on the recent integration of the Soar cognitive architecture with both virtual and physical robotic systems. Soar has been used to develop a wide variety of knowledge-rich agents for complex virtual environments, including distributed training environments and interactive computer games. For development and testing in robotic virtual environments, Soar interfaces to a variety of robotic simulators and a simple mobile robot. We have recently made significant extensions to Soar that add new memories and new non-symbolic reasoning to Soar's original symbolic processing, which should significantly improve Soar abilities for control of robots. These extensions include episodic memory, semantic memory, reinforcement learning, and mental imagery. Episodic memory and semantic memory support the learning and recalling of prior events and situations as well as facts about the world. Reinforcement learning provides the ability of the system to tune its procedural knowledge - knowledge about how to do things. Mental imagery supports the use of diagrammatic and visual representations that are critical to support spatial reasoning. We speculate on the future of unmanned systems and the need for cognitive robotics to support dynamic instruction and taskability.

Comparing different types of source memory attributes in dementia of Alzheimer's type.

PubMed

Mammarella, Nicola; Fairfield, Beth; Di Domenico, Alberto

2012-04-01

Source monitoring (SM) refers to our ability to discriminate between memories from different sources. Twenty healthy high-cognitive functioning older adults, 20 healthy low-cognitive functioning older adults, and 20 older adults with dementia of Alzheimer's type (DAT) were asked to perform a series of SM tasks that varied in terms of the to-be-remembered source attribute (perceptual, spatial, temporal, semantic, social, and affective details). Results indicated that older DAT adults had greater difficulty in SM compared to the healthy control groups, especially with spatial and semantic details. Data are discussed in terms of the SM framework and suggest that poor memory for some types of source information may be considered as an important indicator of clinical memory function when assessing for the presence and severity of dementia.

Semantic memory is impaired in patients with unilateral anterior temporal lobe resection for temporal lobe epilepsy.

PubMed

Lambon Ralph, Matthew A; Ehsan, Sheeba; Baker, Gus A; Rogers, Timothy T

2012-01-01

Contemporary clinical and basic neuroscience studies have increasingly implicated the anterior temporal lobe regions, bilaterally, in the formation of coherent concepts. Mounting convergent evidence for the importance of the anterior temporal lobe in semantic memory is found in patients with bilateral anterior temporal lobe damage (e.g. semantic dementia), functional neuroimaging and repetitive transcranial magnetic stimulation studies. If this proposal is correct, then one might expect patients with anterior temporal lobe resection for long-standing temporal lobe epilepsy to be semantically impaired. Such patients, however, do not present clinically with striking comprehension deficits but with amnesia and variable anomia, leading some to conclude that semantic memory is intact in resection for temporal lobe epilepsy and thus casting doubt over the conclusions drawn from semantic dementia and linked basic neuroscience studies. Whilst there is a considerable neuropsychological literature on temporal lobe epilepsy, few studies have probed semantic memory directly, with mixed results, and none have undertaken the same type of systematic investigation of semantic processing that has been conducted with other patient groups. In this study, therefore, we investigated the semantic performance of 20 patients with resection for chronic temporal lobe epilepsy with a full battery of semantic assessments, including more sensitive measures of semantic processing. The results provide a bridge between the current clinical observations about resection for temporal lobe epilepsy and the expectations from semantic dementia and other neuroscience findings. Specifically, we found that on simple semantic tasks, the patients' accuracy fell in the normal range, with the exception that some patients with left resection for temporal lobe epilepsy had measurable anomia. Once the semantic assessments were made more challenging, by probing specific-level concepts, lower frequency/more abstract items or measuring reaction times on semantic tasks versus those on difficulty-matched non-semantic assessments, evidence of a semantic impairment was found in all individuals. We conclude by describing a unified, computationally inspired framework for capturing the variable degrees of semantic impairment found across different patient groups (semantic dementia, temporal lobe epilepsy, glioma and stroke) as well as semantic processing in neurologically intact participants.

Semantic memory is impaired in patients with unilateral anterior temporal lobe resection for temporal lobe epilepsy

PubMed Central

Ehsan, Sheeba; Baker, Gus A.; Rogers, Timothy T.

2012-01-01

Contemporary clinical and basic neuroscience studies have increasingly implicated the anterior temporal lobe regions, bilaterally, in the formation of coherent concepts. Mounting convergent evidence for the importance of the anterior temporal lobe in semantic memory is found in patients with bilateral anterior temporal lobe damage (e.g. semantic dementia), functional neuroimaging and repetitive transcranial magnetic stimulation studies. If this proposal is correct, then one might expect patients with anterior temporal lobe resection for long-standing temporal lobe epilepsy to be semantically impaired. Such patients, however, do not present clinically with striking comprehension deficits but with amnesia and variable anomia, leading some to conclude that semantic memory is intact in resection for temporal lobe epilepsy and thus casting doubt over the conclusions drawn from semantic dementia and linked basic neuroscience studies. Whilst there is a considerable neuropsychological literature on temporal lobe epilepsy, few studies have probed semantic memory directly, with mixed results, and none have undertaken the same type of systematic investigation of semantic processing that has been conducted with other patient groups. In this study, therefore, we investigated the semantic performance of 20 patients with resection for chronic temporal lobe epilepsy with a full battery of semantic assessments, including more sensitive measures of semantic processing. The results provide a bridge between the current clinical observations about resection for temporal lobe epilepsy and the expectations from semantic dementia and other neuroscience findings. Specifically, we found that on simple semantic tasks, the patients’ accuracy fell in the normal range, with the exception that some patients with left resection for temporal lobe epilepsy had measurable anomia. Once the semantic assessments were made more challenging, by probing specific-level concepts, lower frequency/more abstract items or measuring reaction times on semantic tasks versus those on difficulty-matched non-semantic assessments, evidence of a semantic impairment was found in all individuals. We conclude by describing a unified, computationally inspired framework for capturing the variable degrees of semantic impairment found across different patient groups (semantic dementia, temporal lobe epilepsy, glioma and stroke) as well as semantic processing in neurologically intact participants. PMID:22287382

Functional magnetic resonance imaging of semantic memory as a presymptomatic biomarker of Alzheimer's disease risk.

PubMed

Sugarman, Michael A; Woodard, John L; Nielson, Kristy A; Seidenberg, Michael; Smith, J Carson; Durgerian, Sally; Rao, Stephen M

2012-03-01

Extensive research efforts have been directed toward strategies for predicting risk of developing Alzheimer's disease (AD) prior to the appearance of observable symptoms. Existing approaches for early detection of AD vary in terms of their efficacy, invasiveness, and ease of implementation. Several non-invasive magnetic resonance imaging strategies have been developed for predicting decline in cognitively healthy older adults. This review will survey a number of studies, beginning with the development of a famous name discrimination task used to identify neural regions that participate in semantic memory retrieval and to test predictions of several key theories of the role of the hippocampus in memory. This task has revealed medial temporal and neocortical contributions to recent and remote memory retrieval, and it has been used to demonstrate compensatory neural recruitment in older adults, apolipoprotein E ε4 carriers, and amnestic mild cognitive impairment patients. Recently, we have also found that the famous name discrimination task provides predictive value for forecasting episodic memory decline among asymptomatic older adults. Other studies investigating the predictive value of semantic memory tasks will also be presented. We suggest several advantages associated with the use of semantic processing tasks, particularly those based on person identification, in comparison to episodic memory tasks to study AD risk. Future directions for research and potential clinical uses of semantic memory paradigms are also discussed. This article is part of a Special Issue entitled: Imaging Brain Aging and Neurodegenerative disease. Copyright © 2011 Elsevier B.V. All rights reserved.

FN400 potentials are functionally identical to N400 potentials and reflect semantic processing during recognition testing

PubMed Central

Voss, Joel L.; Federmeier, Kara D.

2010-01-01

The “F” in FN400 denotes a more frontal scalp distribution relative to the morphologically similar N400 component—a distinction consistent with the hypothesized distinct roles of FN400 in familiarity memory versus N400 in language. However, no direct comparisons have substantiated these assumed dissimilarities. To this end, we manipulated short-term semantic priming during a recognition test. Semantic priming effects on N400 were indistinguishable from memory effects at the same latency, and semantic priming strongly modulated the “FN400,” despite having no influence on familiarity memory. Thus, no evidence suggested either electrophysiological or functional differences between the N400 and FN400, and findings were contrary to the linking of the “FN400” to familiarity. Instead, it appears that semantic/conceptual priming (reflected in the N400) occurs during recognition tests, and is frequently (mis)labeled as FN400 and attributed to familiarity. PMID:20701709

Episodic future thinking and future-based decision-making in a case of retrograde amnesia.

PubMed

De Luca, Flavia; Benuzzi, Francesca; Bertossi, Elena; Braghittoni, Davide; di Pellegrino, Giuseppe; Ciaramelli, Elisa

2018-02-01

We investigated episodic future thinking (EFT) and future-based cognition and decision-making in patient SG, who developed a dense retrograde amnesia following hypoxia due to a cardiac arrest. Despite intact general cognitive and executive functioning, SG was unable to remember events from his entire lifetime. He had, however, relatively spared anterograde memory and general semantic knowledge. Voxel-based morphometry detected a reduction of gray matter in the thalamus, cerebellum and fusiform gyrus bilaterally, and, at a reduced threshold, in several regions of the autobiographical memory network, including the hippocampi. We show that SG is unable to imagine personal future events, but can imagine fictitious events not self-relevant and not located in subjective time. Despite severely impaired EFT, SG shows normal attitudes towards the future time, and normal delay discounting rates. These findings suggest that retrieval of autobiographical information from long-term memory is necessary for EFT. However, relatively spared anterograde memory and general semantic knowledge may be sufficient to allow construction of fictitious experiences. As well, EFT is not necessary to drive future-oriented cognition and choice. These findings highlight the relation between autobiographical memory and EFT, and the fractionation of human temporal consciousness. Moreover, they contribute to our understanding of retrograde amnesia as an impairment of memory as well as future thinking. Copyright © 2017 Elsevier Ltd. All rights reserved.

Developmental amnesia: effect of age at injury.

PubMed

Vargha-Khadem, F; Salmond, C H; Watkins, K E; Friston, K J; Gadian, D G; Mishkin, M

2003-08-19

Hypoxic-ischemic events sustained within the first year of life can result in developmental amnesia, a disorder characterized by markedly impaired episodic memory and relatively preserved semantic memory, in association with medial temporal pathology that appears to be restricted to the hippocampus. Here we compared children who had hypoxic-ischemic events before 1 year of age (early group, n = 6) with others who showed memory problems after suffering hypoxic-ischemic events between the ages of 6 and 14 years (late group, n = 5). Morphometric analyses of the whole brain revealed that, compared with age-matched controls, both groups had bilateral abnormalities in the hippocampus, putamen, and posterior thalamus, as well as in the right retrosplenial cortex. The two groups also showed similar reductions (approximately 40%) in hippocampal volumes. Neuropsychologically, the only significant differences between the two were on a few tests of immediate memory, where the early group surpassed the late group. The latter measures provided the only clear indication that very early injury can lead to greater functional sparing than injury acquired later in childhood, due perhaps to the greater plasticity of the infant brain. On measures of long-term memory, by contrast, the two groups had highly similar profiles, both showing roughly equivalent preservation of semantic memory combined with marked impairment in episodic memory. It thus appears that, if this selective memory disorder is a special syndrome related to the early occurrence of hypoxia-induced damage, then the effective age at injury for this syndrome extends from birth to puberty.

Flynn effects on sub-factors of episodic and semantic memory: parallel gains over time and the same set of determining factors.

PubMed

Rönnlund, Michael; Nilsson, Lars-Göran

2009-09-01

The study examined the extent to which time-related gains in cognitive performance, so-called Flynn effects, generalize across sub-factors of episodic memory (recall and recognition) and semantic memory (knowledge and fluency). We conducted time-sequential analyses of data drawn from the Betula prospective cohort study, involving four age-matched samples (35-80 years; N=2996) tested on the same battery of memory tasks on either of four occasions (1989, 1995, 1999, and 2004). The results demonstrate substantial time-related improvements on recall and recognition as well as on fluency and knowledge, with a trend of larger gains on semantic as compared with episodic memory [Rönnlund, M., & Nilsson, L. -G. (2008). The magnitude, generality, and determinants of Flynn effects on forms of declarative memory: Time-sequential analyses of data from a Swedish cohort study. Intelligence], but highly similar gains across the sub-factors. Finally, the association with markers of environmental change was similar, with evidence that historical increases in quantity of schooling was a main driving force behind the gains, both on the episodic and semantic sub-factors. The results obtained are discussed in terms of brain regions involved.

Reduced Short-Term Memory Span in Aphasia and Susceptibility to Interference: Contribution of Material-Specific Maintenance Deficits

PubMed Central

Barde, Laura H.F.; Schwartz, Myrna F.; Chrysikou, Evangelia G.; Thompson-Schill, Sharon L.

2010-01-01

Semantic short-term memory (STM) deficits have been traditionally defined as an inability to maintain semantic representations over a delay (R. Martin, Shelton & Yaffee, 1994). Yet some patients with semantic STM deficits make numerous intrusions of items from previously presented lists, thus presenting an interesting paradox: Why should an inability to maintain semantic representations produce an increase in intrusions from earlier lists? In this study, we investigated the relationship between maintenance deficits and susceptibility to interference in a group of 20 aphasic patients characterized with weak semantic or weak phonological STM. Patients and matched control participants performed a modified item-recognition task designed to elicit semantic or phonological interference from list items located one, two, or three trials back (Hamilton & R. Martin, 2007). Controls demonstrated significant effects of interference in both versions of the task. Interference in patients was predicted by the type and severity of their STM deficit; that is, shorter semantic spans were associated with greater semantic interference and shorter phonological spans were associated with greater phonological interference. We interpret these results through a new perspective, the reactivation hypothesis, and we discuss their importance for accounts emphasizing the contribution of maintenance mechanisms for STM impairments in aphasia as well as susceptibility to interference. PMID:19925813

Semantic Memory in the Clinical Progression of Alzheimer Disease.

PubMed

Tchakoute, Christophe T; Sainani, Kristin L; Henderson, Victor W

2017-09-01

Semantic memory measures may be useful in tracking and predicting progression of Alzheimer disease. We investigated relationships among semantic memory tasks and their 1-year predictive value in women with Alzheimer disease. We conducted secondary analyses of a randomized clinical trial of raloxifene in 42 women with late-onset mild-to-moderate Alzheimer disease. We assessed semantic memory with tests of oral confrontation naming, category fluency, semantic recognition and semantic naming, and semantic density in written narrative discourse. We measured global cognition (Alzheimer Disease Assessment Scale, cognitive subscale), dementia severity (Clinical Dementia Rating sum of boxes), and daily function (Activities of Daily Living Inventory) at baseline and 1 year. At baseline and 1 year, most semantic memory scores correlated highly or moderately with each other and with global cognition, dementia severity, and daily function. Semantic memory task performance at 1 year had worsened one-third to one-half standard deviation. Factor analysis of baseline test scores distinguished processes in semantic and lexical retrieval (semantic recognition, semantic naming, confrontation naming) from processes in lexical search (semantic density, category fluency). The semantic-lexical retrieval factor predicted global cognition at 1 year. Considered separately, baseline confrontation naming and category fluency predicted dementia severity, while semantic recognition and a composite of semantic recognition and semantic naming predicted global cognition. No individual semantic memory test predicted daily function. Semantic-lexical retrieval and lexical search may represent distinct aspects of semantic memory. Semantic memory processes are sensitive to cognitive decline and dementia severity in Alzheimer disease.

The (lack of) effect of dynamic visual noise on the concreteness effect in short-term memory.

PubMed

Castellà, Judit; Campoy, Guillermo

2018-05-17

It has been suggested that the concreteness effect in short-term memory (STM) is a consequence of concrete words having more distinctive and richer semantic representations. The generation and storage of visual codes in STM could also play a crucial role on the effect because concrete words are more imaginable than abstract words. If this were the case, the introduction of a visual interference task would be expected to disrupt recall of concrete words. A Dynamic Visual Noise (DVN) display, which has been proven to eliminate the concreteness effect on long-term memory (LTM), was presented along encoding of concrete and abstract words in a STM serial recall task. Results showed a main effect of word type, with more item errors in abstract words, a main effect of DVN, which impaired global performance due to more order errors, but no interaction, suggesting that DVN did not have any impact on the concreteness effect. These findings are discussed in terms of LTM participation through redintegration processes and in terms of the language-based models of verbal STM.

Impaired Semantic Knowledge Underlies the Reduced Verbal Short-Term Storage Capacity in Alzheimer's Disease

ERIC Educational Resources Information Center

Peters, Frederic; Majerus, Steve; De Baerdemaeker, Julie; Salmon, Eric; Collette, Fabienne

2009-01-01

A decrease in verbal short-term memory (STM) capacity is consistently observed in patients with Alzheimer's disease (AD). Although this impairment has been mainly attributed to attentional deficits during encoding and maintenance, the progressive deterioration of semantic knowledge in early stages of AD may also be an important determinant of poor…

Semantic contribution to verbal short-term memory: are pleasant words easier to remember than neutral words in serial recall and serial recognition?

PubMed

Monnier, Catherine; Syssau, Arielle

2008-01-01

In the four experiments reported here, we examined the role of word pleasantness on immediate serial recall and immediate serial recognition. In Experiment 1, we compared verbal serial recall of pleasant and neutral words, using a limited set of items. In Experiment 2, we replicated Experiment 1 with an open set of words (i.e., new items were used on every trial). In Experiments 3 and 4, we assessed immediate serial recognition of pleasant and neutral words, using item sets from Experiments 1 and 2. Pleasantness was found to have a facilitation effect on both immediate serial recall and immediate serial recognition. This study supplies some new supporting arguments in favor of a semantic contribution to verbal short-term memory performance. The pleasantness effect observed in immediate serial recognition showed that, contrary to a number of earlier findings, performance on this task can also turn out to be dependent on semantic factors. The results are discussed in relation to nonlinguistic and psycholinguistic models of short-term memory.

Memory integration in amnesia: prior knowledge supports verbal short-term memory.

PubMed

Race, Elizabeth; Palombo, Daniela J; Cadden, Margaret; Burke, Keely; Verfaellie, Mieke

2015-04-01

Short-term memory (STM) and long-term memory (LTM) have traditionally been considered cognitively distinct. However, it is known that STM can improve when to-be-remembered information appears in contexts that make contact with prior knowledge, suggesting a more interactive relationship between STM and LTM. The current study investigated whether the ability to leverage LTM in support of STM critically depends on the integrity of the hippocampus. Specifically, we investigated whether the hippocampus differentially supports between-domain versus within-domain STM-LTM integration given prior evidence that the representational domain of the elements being integrated in memory is a critical determinant of whether memory performance depends on the hippocampus. In Experiment 1, we investigated hippocampal contributions to within-domain STM-LTM integration by testing whether immediate verbal recall of words improves in MTL amnesic patients when words are presented in familiar verbal contexts (meaningful sentences) compared to unfamiliar verbal contexts (random word lists). Patients demonstrated a robust sentence superiority effect, whereby verbal STM performance improved in familiar compared to unfamiliar verbal contexts, and the magnitude of this effect did not differ from that in controls. In Experiment 2, we investigated hippocampal contributions to between-domain STM-LTM integration by testing whether immediate verbal recall of digits improves in MTL amnesic patients when digits are presented in a familiar visuospatial context (a typical keypad layout) compared to an unfamiliar visuospatial context (a random keypad layout). Immediate verbal recall improved in both patients and controls when digits were presented in the familiar compared to the unfamiliar keypad array, indicating a preserved ability to integrate activated verbal information with stored visuospatial knowledge. Together, these results demonstrate that immediate verbal recall in amnesia can benefit from two distinct types of semantic support, verbal and visuospatial, and that the hippocampus is not critical for leveraging stored semantic knowledge to improve memory performance. Copyright © 2015 Elsevier Ltd. All rights reserved.

Memory integration in amnesia: Prior knowledge supports verbal short-term memory

PubMed Central

Race, Elizabeth; Palombo, Daniela J.; Cadden, Margaret; Burke, Keely; Verfaellie, Mieke

2015-01-01

Short-term memory (STM) and long-term memory (LTM) have traditionally been considered cognitively distinct. However, it is known that STM can improve when to-be-remembered information appears in contexts that make contact with prior knowledge, suggesting a more interactive relationship between STM and LTM. The current study investigated whether the ability to leverage LTM in support of STM critically depends on the integrity of the hippocampus. Specifically, we investigated whether the hippocampus differentially supports between-domain versus within-domain STM–LTM integration given prior evidence that the representational domain of the elements being integrated in memory is a critical determinant of whether memory performance depends on the hippocampus. In Experiment 1, we investigated hippocampal contributions to within-domain STM–LTM integration by testing whether immediate verbal recall of words improves in MTL amnesic patients when words are presented in familiar verbal contexts (meaningful sentences) compared to unfamiliar verbal contexts (random word lists). Patients demonstrated a robust sentence superiority effect, whereby verbal STM performance improved in familiar compared to unfamiliar verbal contexts, and the magnitude of this effect did not differ from that in controls. In Experiment 2, we investigated hippocampal contributions to between-domain STM–LTM integration by testing whether immediate verbal recall of digits improves in MTL amnesic patients when digits are presented in a familiar visuospatial context (a typical keypad layout) compared to an unfamiliar visuospatial context (a random keypad layout). Immediate verbal recall improved in both patients and controls when digits were presented in the familiar compared to the unfamiliar keypad array, indicating a preserved ability to integrate activated verbal information with stored visuospatial knowledge. Together, these results demonstrate that immediate verbal recall in amnesia can benefit from two distinct types of semantic support, verbal and visuospatial, and that the hippocampus is not critical for leveraging stored semantic knowledge to improve memory performance. PMID:25752585

Priming Effects in Word-Fragment Completion Are Independent of Recognition Memory.

ERIC Educational Resources Information Center

Tulving, Endel; And Others

1982-01-01

Since the priming effects described in this article were independent of episodic memory, and since there were problems with their interpretation in terms of modifications of semantic memory, it is felt that they reflect the operation of some other, as yet little understood, memory system. (Author/PN)

The role of the frontal cortex in memory: an investigation of the Von Restorff effect

PubMed Central

Elhalal, Anat; Davelaar, Eddy J.; Usher, Marius

2014-01-01

Evidence from neuropsychology and neuroimaging indicate that the pre-frontal cortex (PFC) plays an important role in human memory. Although frontal patients are able to form new memories, these memories appear qualitatively different from those of controls by lacking distinctiveness. Neuroimaging studies of memory indicate activation in the PFC under deep encoding conditions, and under conditions of semantic elaboration. Based on these results, we hypothesize that the PFC enhances memory by extracting differences and commonalities in the studied material. To test this hypothesis, we carried out an experimental investigation to test the relationship between the PFC-dependent factors and semantic factors associated with common and specific features of words. These experiments were performed using Free-Recall of word lists with healthy adults, exploiting the correlation between PFC function and fluid intelligence. As predicted, a correlation was found between fluid intelligence and the Von-Restorff effect (better memory for semantic isolates, e.g., isolate “cat” within category members of “fruit”). Moreover, memory for the semantic isolate was found to depend on the isolate's serial position. The isolate item tends to be recalled first, in comparison to non-isolates, suggesting that the process interacts with short term memory. These results are captured within a computational model of free recall, which includes a PFC mechanism that is sensitive to both commonality and distinctiveness, sustaining a trade-off between the two. PMID:25018721

Hippocampal coupling with cortical and subcortical structures in the context of memory consolidation.

PubMed

Skelin, Ivan; Kilianski, Scott; McNaughton, Bruce L

2018-04-13

Memory consolidation is a gradual process through which episodic memories become incorporated into long-term 'semantic' representations. It likely involves reactivation of neural activity encoding the recent experience during non-REM sleep. A critical prerequisite for memory consolidation is precise coordination of reactivation events between the hippocampus and cortical/subcortical structures, facilitated by the coupling of local field potential (LFP) oscillations (slow oscillations, sleep spindles and sharp wave/ripples) between these structures. We review the rapidly expanding literature on the qualitative and quantitative aspects of hippocampal oscillatory and neuronal coupling with cortical/subcortical structures in the context of memory reactivation. Reactivation in the hippocampus and cortical/subcortical structures is tightly coupled with sharp wave/ripples. Hippocampal-cortical/subcortical coupling is rich in dimensionality and this dimensionality is likely underestimated due to the limitations of the current methodology. Copyright © 2018 Elsevier Inc. All rights reserved.

Differentiation of perceptual and semantic subsequent memory effects using an orthographic paradigm.

PubMed

Kuo, Michael C C; Liu, Karen P Y; Ting, Kin Hung; Chan, Chetwyn C H

2012-11-27

This study aimed to differentiate perceptual and semantic encoding processes using subsequent memory effects (SMEs) elicited by the recognition of orthographs of single Chinese characters. Participants studied a series of Chinese characters perceptually (by inspecting orthographic components) or semantically (by determining the object making sounds), and then made studied or unstudied judgments during the recognition phase. Recognition performance in terms of d-prime measure in the semantic condition was higher, though not significant, than that of the perceptual condition. The between perceptual-semantic condition differences in SMEs at P550 and late positive component latencies (700-1000ms) were not significant in the frontal area. An additional analysis identified larger SME in the semantic condition during 600-1000ms in the frontal pole regions. These results indicate that coordination and incorporation of orthographic information into mental representation is essential to both task conditions. The differentiation was also revealed in earlier SMEs (perceptual>semantic) at N3 (240-360ms) latency, which is a novel finding. The left-distributed N3 was interpreted as more efficient processing of meaning with semantically learned characters. Frontal pole SMEs indicated strategic processing by executive functions, which would further enhance memory. Copyright © 2012 Elsevier B.V. All rights reserved.

Levels of processing and picture memory: the physical superiority effect.

PubMed

Intraub, H; Nicklos, S

1985-04-01

Six experiments studied the effect of physical orienting questions (e.g., "Is this angular?") and semantic orienting questions (e.g., "Is this edible?") on memory for unrelated pictures at stimulus durations ranging from 125-2,000 ms. Results ran contrary to the semantic superiority "rule of thumb," which is based primarily on verbal memory experiments. Physical questions were associated with better free recall and cued recall of a diverse set of visual scenes (Experiments 1, 2, and 4). This occurred both when general and highly specific semantic questions were used (Experiments 1 and 2). Similar results were obtained when more simplistic visual stimuli--photographs of single objects--were used (Experiments 5 and 6). As in the case of the semantic superiority effect with words, the physical superiority effect for pictures was eliminated or reversed when the same physical questions were repeated throughout the session (Experiments 4 and 6). Conflicts with results of previous levels of processing experiments with words and nonverbal stimuli (e.g., faces) are explained in terms of the sensory-semantic model (Nelson, Reed, & McEvoy, 1977). Implications for picture memory research and the levels of processing viewpoint are discussed.

Visual novel stimuli in an ERP novelty oddball paradigm: effects of familiarity on repetition and recognition memory.

PubMed

Cycowicz, Yael M; Friedman, David

2007-01-01

The orienting response, the brain's reaction to novel and/or out of context familiar events, is reflected by the novelty P3 of the ERP. Contextually novel events also engender high rates of recognition memory. We examined, under incidental and intentional conditions, the effects of visual symbol familiarity on the novelty P3 recorded during an oddball task and on the parietal episodic memory (EM) effect, an index of recollection. Repetition of familiar, but not unfamiliar, symbols elicited a reduction in the novelty P3. Better recognition performance for the familiar symbols was associated with a robust parietal EM effect, which was absent for the unfamiliar symbols in the incidental task. These data demonstrate that processing of novel events depends on expectation and whether stimuli have preexisting representations in long-term semantic memory.

Frontal lobe damage impairs process and content in semantic memory: evidence from category-specific effects in progressive non-fluent aphasia.

PubMed

Reilly, Jamie; Rodriguez, Amy D; Peelle, Jonathan E; Grossman, Murray

2011-06-01

Portions of left inferior frontal cortex have been linked to semantic memory both in terms of the content of conceptual representation (e.g., motor aspects in an embodied semantics framework) and the cognitive processes used to access these representations (e.g., response selection). Progressive non-fluent aphasia (PNFA) is a neurodegenerative condition characterized by progressive atrophy of left inferior frontal cortex. PNFA can, therefore, provide a lesion model for examining the impact of frontal lobe damage on semantic processing and content. In the current study we examined picture naming in a cohort of PNFA patients across a variety of semantic categories. An embodied approach to semantic memory holds that sensorimotor features such as self-initiated action may assume differential importance for the representation of manufactured artifacts (e.g., naming hand tools). Embodiment theories might therefore predict that patients with frontal damage would be differentially impaired on manufactured artifacts relative to natural kinds, and this prediction was borne out. We also examined patterns of naming errors across a wide range of semantic categories and found that naming error distributions were heterogeneous. Although PNFA patients performed worse overall on naming manufactured artifacts, there was no reliable relationship between anomia and manipulability across semantic categories. These results add to a growing body of research arguing against a purely sensorimotor account of semantic memory, suggesting instead a more nuanced balance of process and content in how the brain represents conceptual knowledge. Copyright © 2010 Elsevier Srl. All rights reserved.

Dynamic memory searches: Selective output interference for the memory of facts.

PubMed

Aue, William R; Criss, Amy H; Prince, Melissa A

2015-12-01

The benefits of testing on later memory performance are well documented; however, the manner in which testing harms memory performance is less well understood. This research is concerned with the finding that accuracy decreases over the course of testing, a phenomena termed "output interference" (OI). OI has primarily been investigated with episodic memory, but there is limited research investigating OI in measures of semantic memory (i.e., knowledge). In the current study, participants were twice tested for their knowledge of factual questions; they received corrective feedback during the first test. No OI was observed during the first test, when participants presumably searched semantic memory to answer the general-knowledge questions. During the second test, OI was observed. Conditional analyses of Test 2 performance revealed that OI was largely isolated to questions answered incorrectly during Test 1. These were questions for which participants needed to rely on recent experience (i.e., the feedback in episodic memory) to respond correctly. One possible explanation is that episodic memory is more susceptible to the sort of interference generated during testing (e.g., gradual changes in context, encoding/updating of items) relative to semantic memory. Alternative explanations are considered.

Personal semantics: Is it distinct from episodic and semantic memory? An electrophysiological study of memory for autobiographical facts and repeated events in honor of Shlomo Bentin.

PubMed

Renoult, Louis; Tanguay, Annick; Beaudry, Myriam; Tavakoli, Paniz; Rabipour, Sheida; Campbell, Kenneth; Moscovitch, Morris; Levine, Brian; Davidson, Patrick S R

2016-03-01

Declarative memory is thought to consist of two independent systems: episodic and semantic. Episodic memory represents personal and contextually unique events, while semantic memory represents culturally-shared, acontextual factual knowledge. Personal semantics refers to aspects of declarative memory that appear to fall somewhere in between the extremes of episodic and semantic. Examples include autobiographical knowledge and memories of repeated personal events. These two aspects of personal semantics have been studied little and rarely compared to both semantic and episodic memory. We recorded the event-related potentials (ERPs) of 27 healthy participants while they verified the veracity of sentences probing four types of questions: general (i.e., semantic) facts, autobiographical facts, repeated events, and unique (i.e., episodic) events. Behavioral results showed equivalent reaction times in all 4 conditions. True sentences were verified faster than false sentences, except for unique events for which no significant difference was observed. Electrophysiological results showed that the N400 (which is classically associated with retrieval from semantic memory) was maximal for general facts and the LPC (which is classically associated with retrieval from episodic memory) was maximal for unique events. For both ERP components, the two personal semantic conditions (i.e., autobiographical facts and repeated events) systematically differed from semantic memory. In addition, N400 amplitudes also differentiated autobiographical facts from unique events. Autobiographical facts and repeated events did not differ significantly from each other but their corresponding scalp distributions differed from those associated with general facts. Our results suggest that the neural correlates of personal semantics can be distinguished from those of semantic and episodic memory, and may provide clues as to how unique events are transformed to semantic memory. Copyright © 2015 Elsevier Ltd. All rights reserved.

Semantic and Syntactic Associations During Word Search Modulate the Relationship Between Attention and Subsequent Memory.

PubMed

Zhou, Wei; Mo, Fei; Zhang, Yunhong; Ding, Jinhong

2017-01-01

Two experiments were conducted to investigate how linguistic information influences attention allocation in visual search and memory for words. In Experiment 1, participants searched for the synonym of a cue word among five words. The distractors included one antonym and three unrelated words. In Experiment 2, participants were asked to judge whether the five words presented on the screen comprise a valid sentence. The relationships among words were sentential, semantically related or unrelated. A memory recognition task followed. Results in both experiments showed that linguistically related words produced better memory performance. We also found that there were significant interactions between linguistic relation conditions and memorization on eye-movement measures, indicating that good memory for words relied on frequent and long fixations during search in the unrelated condition but to a much lesser extent in linguistically related conditions. We conclude that semantic and syntactic associations attenuate the link between overt attention allocation and subsequent memory performance, suggesting that linguistic relatedness can somewhat compensate for a relative lack of attention during word search.

BDNF and TNF-α polymorphisms in memory.

PubMed

Yogeetha, B S; Haupt, L M; McKenzie, K; Sutherland, H G; Okolicsyani, R K; Lea, R A; Maher, B H; Chan, R C K; Shum, D H K; Griffiths, L R

2013-09-01

Here, we investigate the genetic basis of human memory in healthy individuals and the potential role of two polymorphisms, previously implicated in memory function. We have explored aspects of retrospective and prospective memory including semantic, short term, working and long-term memory in conjunction with brain derived neurotrophic factor (BDNF) and tumor necrosis factor-alpha (TNF-α). The memory scores for healthy individuals in the population were obtained for each memory type and the population was genotyped via restriction fragment length polymorphism for the BDNF rs6265 (Val66Met) SNP and via pyrosequencing for the TNF-α rs113325588 SNP. Using univariate ANOVA, a significant association of the BDNF polymorphism with visual and spatial memory retention and a significant association of the TNF-α polymorphism was observed with spatial memory retention. In addition, a significant interactive effect between BDNF and TNF-α polymorphisms was observed in spatial memory retention. In practice visual memory involves spatial information and the two memory systems work together, however our data demonstrate that individuals with the Val/Val BDNF genotype have poorer visual memory but higher spatial memory retention, indicating a level of interaction between TNF-α and BDNF in spatial memory retention. This is the first study to use genetic analysis to determine the interaction between BDNF and TNF-α in relation to memory in normal adults and provides important information regarding the effect of genetic determinants and gene interactions on human memory.

Professional Music Training and Novel Word Learning: From Faster Semantic Encoding to Longer-lasting Word Representations.

PubMed

Dittinger, Eva; Barbaroux, Mylène; D'Imperio, Mariapaola; Jäncke, Lutz; Elmer, Stefan; Besson, Mireille

2016-10-01

On the basis of previous results showing that music training positively influences different aspects of speech perception and cognition, the aim of this series of experiments was to test the hypothesis that adult professional musicians would learn the meaning of novel words through picture-word associations more efficiently than controls without music training (i.e., fewer errors and faster RTs). We also expected musicians to show faster changes in brain electrical activity than controls, in particular regarding the N400 component that develops with word learning. In line with these hypotheses, musicians outperformed controls in the most difficult semantic task. Moreover, although a frontally distributed N400 component developed in both groups of participants after only a few minutes of novel word learning, in musicians this frontal distribution rapidly shifted to parietal scalp sites, as typically found for the N400 elicited by known words. Finally, musicians showed evidence for better long-term memory for novel words 5 months after the main experimental session. Results are discussed in terms of cascading effects from enhanced perception to memory as well as in terms of multifaceted improvements of cognitive processing due to music training. To our knowledge, this is the first report showing that music training influences semantic aspects of language processing in adults. These results open new perspectives for education in showing that early music training can facilitate later foreign language learning. Moreover, the design used in the present experiment can help to specify the stages of word learning that are impaired in children and adults with word learning difficulties.

Semantic and episodic memory in children with temporal lobe epilepsy: do they relate to literacy skills?

PubMed

Lah, Suncica; Smith, Mary Lou

2014-01-01

Children with temporal lobe epilepsy are at risk for deficits in new learning (episodic memory) and literacy skills. Semantic memory deficits and double dissociations between episodic and semantic memory have recently been found in this patient population. In the current study we investigate whether impairments of these 2 distinct memory systems relate to literacy skills. 57 children with unilateral temporal lobe epilepsy completed tests of verbal memory (episodic and semantic) and literacy skills (reading and spelling accuracy, and reading comprehension). For the entire group, semantic memory explained over 30% of variance in each of the literacy domains. Episodic memory explained a significant, but rather small proportion (< 10%) of variance in reading and spelling accuracy, but not in reading comprehension. Moreover, when children with opposite patterns of specific memory impairments (intact semantic/impaired episodic, intact episodic/impaired semantic) were compared, significant reductions in literacy skills were evident only in children with semantic memory impairments, but not in children with episodic memory impairments relative to the norms and to children with temporal lobe epilepsy who had intact memory. Our study provides the first evidence for differential relations between episodic and semantic memory impairments and literacy skills in children with temporal lobe epilepsy. As such, it highlights the urgent need to consider semantic memory deficits in management of children with temporal lobe epilepsy and undertake further research into the nature of reading difficulties of children with semantic memory impairments.

Goal-Driven Autonomy and Robust Architecture for Long-Duration Missions (Year 1: 1 July 2013 - 31 July 2014)

DTIC Science & Technology

2014-09-30

Mental Domain = Ω Goal Management goal change goal input World =Ψ Memory Mission & Goals( ) World Model (-Ψ) Episodic Memory Semantic Memory ...Activations Trace Meta-Level Control Introspective Monitoring Memory Reasoning Trace ( ) Strategies Episodic Memory Metaknowledge Self Model...it is from incorrect or missing memory associations (i.e., indices). Similarly, correct information may exist in the input stream, but may not be

The relational luring effect: Retrieval of relational information during associative recognition.

PubMed

Popov, Vencislav; Hristova, Penka; Anders, Royce

2017-05-01

Here we argue that semantic relations (e.g., works in: nurse-hospital) have abstract independent representations in long-term memory (LTM) and that the same representation is accessed by all exemplars of a specific relation. We present evidence from 2 associative recognition experiments that uncovered a novel relational luring effect (RLE) in recognition memory. Participants studied word pairs, and then discriminated between intact (old) pairs and recombined lures. In the first experiment participants responded more slowly to lures that were relationally similar (table-cloth) to studied pairs (floor-carpet), in contrast to relationally dissimilar lures (pipe-water). Experiment 2 extended the RLE by showing a continuous effect of relational lure strength on recognition times (RTs), false alarms, and hits. It used a continuous pair recognition task, where each recombined lure or target could be preceded by 0, 1, 2, 3 or 4 different exemplars of the same relation. RTs and false alarms increased linearly with the number of different previously seen relationally similar pairs. Moreover, more typical exemplars of a given relation lead to a stronger RLE. Finally, hits for intact pairs also rose with the number of previously studied different relational instances. These results suggest that semantic relations exist as independent representations in LTM and that during associative recognition these representations can be a spurious source of familiarity. We discuss the implications of the RLE for current models of semantic and episodic memory, unitization in associative recognition, analogical reasoning and retrieval, as well as constructive memory research. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

An fMRI comparison of neural activity associated with recognition of familiar melodies in younger and older adults

PubMed Central

Sikka, Ritu; Cuddy, Lola L.; Johnsrude, Ingrid S.; Vanstone, Ashley D.

2015-01-01

Several studies of semantic memory in non-musical domains involving recognition of items from long-term memory have shown an age-related shift from the medial temporal lobe structures to the frontal lobe. However, the effects of aging on musical semantic memory remain unexamined. We compared activation associated with recognition of familiar melodies in younger and older adults. Recognition follows successful retrieval from the musical lexicon that comprises a lifetime of learned musical phrases. We used the sparse-sampling technique in fMRI to determine the neural correlates of melody recognition by comparing activation when listening to familiar vs. unfamiliar melodies, and to identify age differences. Recognition-related cortical activation was detected in the right superior temporal, bilateral inferior and superior frontal, left middle orbitofrontal, bilateral precentral, and left supramarginal gyri. Region-of-interest analysis showed greater activation for younger adults in the left superior temporal gyrus and for older adults in the left superior frontal, left angular, and bilateral superior parietal regions. Our study provides powerful evidence for these musical memory networks due to a large sample (N = 40) that includes older adults. This study is the first to investigate the neural basis of melody recognition in older adults and to compare the findings to younger adults. PMID:26500480

Episodic memory, semantic memory, and amnesia.

PubMed

Squire, L R; Zola, S M

1998-01-01

Episodic memory and semantic memory are two types of declarative memory. There have been two principal views about how this distinction might be reflected in the organization of memory functions in the brain. One view, that episodic memory and semantic memory are both dependent on the integrity of medial temporal lobe and midline diencephalic structures, predicts that amnesic patients with medial temporal lobe/diencephalic damage should be proportionately impaired in both episodic and semantic memory. An alternative view is that the capacity for semantic memory is spared, or partially spared, in amnesia relative to episodic memory ability. This article reviews two kinds of relevant data: 1) case studies where amnesia has occurred early in childhood, before much of an individual's semantic knowledge has been acquired, and 2) experimental studies with amnesic patients of fact and event learning, remembering and knowing, and remote memory. The data provide no compelling support for the view that episodic and semantic memory are affected differently in medial temporal lobe/diencephalic amnesia. However, episodic and semantic memory may be dissociable in those amnesic patients who additionally have severe frontal lobe damage.

Remote memory in a patient with amnesia due to hypoxia.

PubMed

Beatty, W W; Salmon, D P; Bernstein, N; Butters, N

1987-08-01

It has been suggested that amnesic patients suffer a selective loss of episodic memory while semantic memory remains well preserved. To assess the validity of this idea we studied remote memory in an amnesic patient, (M.R.L.), using several different measures that differ in the extent to which they engage episodic or semantic memory. On two different versions of the Albert et al. (1979) remote memory battery M.R.L. displayed severe retrograde amnesia (RA) extending backwards in time for about 15 years with excellent preservation of older memories. With standard recall instructions his overall performance on the Crovitz test of autobiographical memory was impaired and all of M.R.L.'s specific, temporally dated memories were given from the first half of his life. When asked to reconstruct his past residential history in detail, M.R.L. provide specific and generally accurate information for residences occupied from his boyhood until 1970, but thereafter his memory became quite unreliable. On a test of knowledge of terms commonly employed in the surveying profession, in which he worked for the past 20 years, M.R.L.'s performance was also impaired. The consistent pattern of RA displayed by this patient on all of the tests of remote memory indicates that both episodic and semantic memory are impaired in amnesia.

Semantic and phonological information in sentence recall: converging psycholinguistic and neuropsychological evidence.

PubMed

Schweppe, Judith; Rummer, Ralf; Bormann, Tobias; Martin, Randi C

2011-12-01

We present one experiment and a neuropsychological case study to investigate to what extent phonological and semantic representations contribute to short-term sentence recall. We modified Potter and Lombardi's (1990) intrusion paradigm, in which retention of a list interferes with sentence recall such that on the list a semantically related lure is presented, which is expected to intrude into sentence recall. In our version, lure words are either semantically related to target words in the sentence or semantically plus phonologically related. With healthy participants, intrusions are more frequent when lure and target overlap phonologically in addition to semantically than when they solely overlap semantically. When this paradigm is applied to a patient with a phonological short-term memory impairment, both lure types induce the same amount of intrusions. These findings indicate that usually phonological information is retained in sentence recall in addition to semantic information.

Neural correlates of remembering/knowing famous people: an event-related fMRI study.

PubMed

Denkova, Ekaterina; Botzung, Anne; Manning, Lilianne

2006-01-01

It has been suggested that knowledge about some famous people depends on both a generic semantic component and an autobiographical component [Westmacott, R., & Moscovitch, M. (2003). The contribution of autobiographical significance to semantic memory. Memory and Cognition, 31, 761-774]. The neuropsychological studies of semantic dementia (SD) and Alzheimer disease (AD) demonstrated that the two aspects are very likely to be mediated by different brain structures, with the episodic component being highly dependent upon the integrity of the medial temporal lobe (MTL) [Westmacott, R., Black, S. E., Freedman, M., & Moscovitch, M. (2004). The contribution of autobiographical significance to semantic memory: Evidence from Alzheimer's disease, semantic dementia, and amnesia. Neuropsychologia, 42, 25-48]. Using an fMRI design in healthy participants, we aimed: (i) to investigate the pattern of brain activations sustaining the autobiographical and the semantic aspects of knowledge about famous persons. Moreover, (ii) we examined if the stimulus material (face/name) influences the lateralisation of the cerebral networks. Our findings suggested that different patterns of activation corresponded to the presence or absence of personal significance linked to semantic knowledge; MTL was engaged only in the former case. Although choice of stimulus material did not influence the hemispheric lateralisation in "classical" terms, it did play a role in engaging different cerebral regions.

Forced to remember: when memory is biased by salient information.

PubMed

Santangelo, Valerio

2015-04-15

The last decades have seen a rapid growing in the attempt to understand the key factors involved in the internal memory representation of the external world. Visual salience have been found to provide a major contribution in predicting the probability for an item/object embedded in a complex setting (i.e., a natural scene) to be encoded and then remembered later on. Here I review the existing literature highlighting the impact of perceptual- (based on low-level sensory features) and semantics-related salience (based on high-level knowledge) on short-term memory representation, along with the neural mechanisms underpinning the interplay between these factors. The available evidence reveal that both perceptual- and semantics-related factors affect attention selection mechanisms during the encoding of natural scenes. Biasing internal memory representation, both perceptual and semantics factors increase the probability to remember high- to the detriment of low-saliency items. The available evidence also highlight an interplay between these factors, with a reduced impact of perceptual-related salience in biasing memory representation as a function of the increasing availability of semantics-related salient information. The neural mechanisms underpinning this interplay involve the activation of different portions of the frontoparietal attention control network. Ventral regions support the assignment of selection/encoding priorities based on high-level semantics, while the involvement of dorsal regions reflects priorities assignment based on low-level sensory features. Copyright © 2015 Elsevier B.V. All rights reserved.

Morphological processing with deficient phonological short-term memory.

PubMed

Kavé, Gitit; Ze'ev, Hagit Bar; Lev, Anita

2007-07-01

This paper investigates the processing of Hebrew derivational morphology in an individual (S.E.) with deficient phonological short-term memory. In comparison to 10 age- and education-matched men, S.E. was impaired on digit span tasks and demonstrated no recency effect in word list recall. S.E. had low word retention span, but he exhibited phonological similarity and word length effects. His ability to make lexical decisions was intact. In a paired-associate test S.E. successfully learned semantically and morphologically related pairs but not phonologically related pairs, and his learning of nonwords was facilitated by the presence of Hebrew consonant roots. Semantic and morphological similarity enhanced immediate word recall. Results show that S.E. is capable of conducting morphological decomposition of Hebrew-derived words despite his phonological deficit, suggesting that transient maintenance of morphological constituents is independent of temporary storage and rehearsal of phonological codes, and that each is processed separately within short-term memory.

Effects of semantic relatedness on recall of stimuli preceding emotional oddballs.

PubMed

Smith, Ryan M; Beversdorf, David Q

2008-07-01

Semantic and episodic memory networks function as highly interconnected systems, both relying on the hippocampal/medial temporal lobe complex (HC/MTL). Episodic memory encoding triggers the retrieval of semantic information, serving to incorporate contextual relationships between the newly acquired memory and existing semantic representations. While emotional material augments episodic memory encoding at the time of stimulus presentation, interactions between emotion and semantic memory that contribute to subsequent episodic recall are not well understood. Using a modified oddball task, we examined the modulatory effects of negative emotion on semantic interactions with episodic memory by measuring the free-recall of serially presented neutral or negative words varying in semantic relatedness. We found increased free-recall for words related to and preceding emotionally negative oddballs, suggesting that negative emotion can indirectly facilitate episodic free-recall by enhancing semantic contributions during encoding. Our findings demonstrate the ability of emotion and semantic memory to interact to mutually enhance free-recall.

Hippocampal activation during retrieval of spatial context from episodic and semantic memory.

PubMed

Hoscheidt, Siobhan M; Nadel, Lynn; Payne, Jessica; Ryan, Lee

2010-10-15

The hippocampus, a region implicated in the processing of spatial information and episodic memory, is central to the debate concerning the relationship between episodic and semantic memory. Studies of medial temporal lobe amnesic patients provide evidence that the hippocampus is critical for the retrieval of episodic but not semantic memory. On the other hand, recent neuroimaging studies of intact individuals report hippocampal activation during retrieval of both autobiographical memories and semantic information that includes historical facts, famous faces, and categorical information, suggesting that episodic and semantic memory may engage the hippocampus during memory retrieval in similar ways. Few studies have matched episodic and semantic tasks for the degree to which they include spatial content, even though spatial content may be what drives hippocampal activation during semantic retrieval. To examine this issue, we conducted a functional magnetic resonance imaging (fMRI) study in which retrieval of spatial and nonspatial information was compared during an episodic and semantic recognition task. Results show that the hippocampus (1) participates preferentially in the retrieval of episodic memories; (2) is also engaged by retrieval of semantic memories, particularly those that include spatial information. These data suggest that sharp dissociations between episodic and semantic memory may be overly simplistic and that the hippocampus plays a role in the retrieval of spatial content whether drawn from a memory of one's own life experiences or real-world semantic knowledge. Published by Elsevier B.V.

Lexicality Effects in Word and Nonword Recall of Semantic Dementia and Progressive Nonfluent Aphasia

PubMed Central

Reilly, Jamie; Troche, Joshua; Chatel, Alison; Park, Hyejin; Kalinyak-Fliszar, Michelene; Antonucci, Sharon M.; Martin, Nadine

2012-01-01

Background Verbal working memory is an essential component of many language functions, including sentence comprehension and word learning. As such, working memory has emerged as a domain of intense research interest both in aphasiology and in the broader field of cognitive neuroscience. The integrity of verbal working memory encoding relies on a fluid interaction between semantic and phonological processes. That is, we encode verbal detail using many cues related to both the sound and meaning of words. Lesion models can provide an effective means of parsing the contributions of phonological or semantic impairment to recall performance. Methods and Procedures We employed the lesion model approach here by contrasting the nature of lexicality errors incurred during recall of word and nonword sequences by 3individuals with progressive nonfluent aphasia (a phonological dominant impairment) compared to that of 2 individuals with semantic dementia (a semantic dominant impairment). We focused on psycholinguistic attributes of correctly recalled stimuli relative to those that elicited a lexicality error (i.e., nonword → word OR word → nonword). Outcomes and results Patients with semantic dementia showed greater sensitivity to phonological attributes (e.g., phoneme length, wordlikeness) of the target items relative to semantic attributes (e.g., familiarity). Patients with PNFA showed the opposite pattern, marked by sensitivity to word frequency, age of acquisition, familiarity, and imageability. Conclusions We interpret these results in favor of a processing strategy such that in the context of a focal phonological impairment patients revert to an over-reliance on preserved semantic processing abilities. In contrast, a focal semantic impairment forces both reliance upon and hypersensitivity to phonological attributes of target words. We relate this interpretation to previous hypotheses about the nature of verbal short-term memory in progressive aphasia. PMID:23486736

Personal semantics: at the crossroads of semantic and episodic memory.

PubMed

Renoult, Louis; Davidson, Patrick S R; Palombo, Daniela J; Moscovitch, Morris; Levine, Brian

2012-11-01

Declarative memory is usually described as consisting of two systems: semantic and episodic memory. Between these two poles, however, may lie a third entity: personal semantics (PS). PS concerns knowledge of one's past. Although typically assumed to be an aspect of semantic memory, it is essentially absent from existing models of knowledge. Furthermore, like episodic memory (EM), PS is idiosyncratically personal (i.e., not culturally-shared). We show that, depending on how it is operationalized, the neural correlates of PS can look more similar to semantic memory, more similar to EM, or dissimilar to both. We consider three different perspectives to better integrate PS into existing models of declarative memory and suggest experimental strategies for disentangling PS from semantic and episodic memory. Copyright © 2012 Elsevier Ltd. All rights reserved.

The general/specific breakdown of semantic memory and the nature of superordinate knowledge: insights from superordinate and basic-level feature norms.

PubMed

Marques, J Frederico

2007-12-01

The deterioration of semantic memory usually proceeds from more specific to more general superordinate categories, although rarer cases of superordinate knowledge impairment have also been reported. The nature of superordinate knowledge and the explanation of these two semantic impairments were evaluated from the analysis of superordinate and basic-level feature norms. The results show that, in comparison to basic-level concepts, superordinate concepts are not generally less informative and have similar feature distinctiveness and proportion of individual sensory features, but their features are less shared by their members. Results are in accord with explanations based on feature connection weights and/or concept confusability for the superordinate advantage cases. Results especially support an explanation for superordinate impairments in terms of higher semantic control requirements as related to features being less shared between concept members. Implications for patients with semantic impairments are also discussed.

THE COGNITIVE NEUROSCIENCE OF WORKING MEMORY

PubMed Central

D’Esposito, Mark; Postle, Bradley R.

2015-01-01

For over 50 years, psychologists and neuroscientists have recognized the importance of a “working memory” to coordinate processing when multiple goals are active, and to guide behavior with information that is not present in the immediate environment. In recent years, psychological theory and cognitive neuroscience data have converged on the idea that information is encoded into working memory via the allocation of attention to internal representations – be they semantic long-term memory (e.g., letters, digits, words), sensory, or motoric. Thus, information-based multivariate analyses of human functional MRI data typically find evidence for the temporary representation of stimuli in regions that also process this information in nonworking-memory contexts. The prefrontal cortex, on the other hand, exerts control over behavior by biasing the salience of mnemonic representations, and adjudicating among competing, context-dependent rules. The “control of the controller” emerges from a complex interplay between PFC and striatal circuits, and ascending dopaminergic neuromodulatory signals. PMID:25251486

Interactions between thalamic and cortical rhythms during semantic memory recall in human

NASA Astrophysics Data System (ADS)

Slotnick, Scott D.; Moo, Lauren R.; Kraut, Michael A.; Lesser, Ronald P.; Hart, John, Jr.

2002-04-01

Human scalp electroencephalographic rhythms, indicative of cortical population synchrony, have long been posited to reflect cognitive processing. Although numerous studies employing simultaneous thalamic and cortical electrode recording in nonhuman animals have explored the role of the thalamus in the modulation of cortical rhythms, direct evidence for thalamocortical modulation in human has not, to our knowledge, been obtained. We simultaneously recorded from thalamic and scalp electrodes in one human during performance of a cognitive task and found a spatially widespread, phase-locked, low-frequency rhythm (7-8 Hz) power decrease at thalamus and scalp during semantic memory recall. This low-frequency rhythm power decrease was followed by a spatially specific, phase-locked, fast-rhythm (21-34 Hz) power increase at thalamus and occipital scalp. Such a pattern of thalamocortical activity reflects a plausible neural mechanism underlying semantic memory recall that may underlie other cognitive processes as well.

Lexical and Semantic Binding in Verbal Short-Term Memory

ERIC Educational Resources Information Center

Jefferies, Elizabeth; Frankish, Clive R.; Ralph, Matthew A. Lambon

2006-01-01

Semantic dementia patients make numerous phoneme migration errors in their immediate serial recall of poorly comprehended words. In this study, similar errors were induced in the word recall of healthy participants by presenting unpredictable mixed lists of words and nonwords. This technique revealed that lexicality, word frequency, imageability,…

Electrophysiological signatures of phonological and semantic maintenance in sentence repetition.

PubMed

Meltzer, Jed A; Kielar, Aneta; Panamsky, Lilia; Links, Kira A; Deschamps, Tiffany; Leigh, Rosie C

2017-08-01

Verbal short-term memory comprises resources for phonological rehearsal, which have been characterized anatomically, and for maintenance of semantic information, which are less understood. Sentence repetition tasks tap both processes interactively. To distinguish brain activity involved in phonological vs. semantic maintenance, we recorded magnetoencephalography during a sentence repetition task, incorporating three manipulations emphasizing one mechanism over the other. Participants heard sentences or word lists and attempted to repeat them verbatim after a 5-second delay. After MEG, participants completed a cued recall task testing how much they remembered of each sentence. Greater semantic engagement relative to phonological rehearsal was hypothesized for 1) sentences vs. word lists, 2) concrete vs. abstract sentences, and 3) well recalled vs. poorly recalled sentences. During auditory perception and the memory delay period, we found highly left-lateralized activation in the form of 8-30 Hz event-related desynchronization. Compared to abstract sentences, concrete sentences recruited posterior temporal cortex bilaterally, demonstrating a neural signature for the engagement of visual imagery in sentence maintenance. Maintenance of arbitrary word lists recruited right hemisphere dorsal regions, reflecting increased demands on phonological rehearsal. Sentences that were ultimately poorly recalled in the post-test also elicited extra right hemisphere activation when they were held in short-term memory, suggesting increased demands on phonological resources. Frontal midline theta oscillations also reflected phonological rather than semantic demand, being increased for word lists and poorly recalled sentences. These findings highlight distinct neural resources for phonological and semantic maintenance, with phonological maintenance associated with stronger oscillatory modulations. Copyright © 2017 Elsevier Inc. All rights reserved.

Dissociating the effects of semantic grouping and rehearsal strategies on event-related brain potentials.

PubMed

Schleepen, T M J; Markus, C R; Jonkman, L M

2014-12-01

The application of elaborative encoding strategies during learning, such as grouping items on similar semantic categories, increases the likelihood of later recall. Previous studies have suggested that stimuli that encourage semantic grouping strategies had modulating effects on specific ERP components. However, these studies did not differentiate between ERP activation patterns evoked by elaborative working memory strategies like semantic grouping and more simple strategies like rote rehearsal. Identification of neurocognitive correlates underlying successful use of elaborative strategies is important to understand better why certain populations, like children or elderly people, have problems applying such strategies. To compare ERP activation during the application of elaborative versus more simple strategies subjects had to encode either four semantically related or unrelated pictures by respectively applying a semantic category grouping or a simple rehearsal strategy. Another goal was to investigate if maintenance of semantically grouped vs. ungrouped pictures modulated ERP-slow waves differently. At the behavioral level there was only a semantic grouping benefit in terms of faster responding on correct rejections (i.e. when the memory probe stimulus was not part of the memory set). At the neural level, during encoding semantic grouping only had a modest specific modulatory effect on a fronto-central Late Positive Component (LPC), emerging around 650 ms. Other ERP components (i.e. P200, N400 and a second Late Positive Component) that had been earlier related to semantic grouping encoding processes now showed stronger modulation by rehearsal than by semantic grouping. During maintenance semantic grouping had specific modulatory effects on left and right frontal slow wave activity. These results stress the importance of careful control of strategy use when investigating the neural correlates of elaborative encoding. Copyright © 2014 Elsevier B.V. All rights reserved.

Cognition and speech-in-noise recognition: the role of proactive interference.

PubMed

Ellis, Rachel J; Rönnberg, Jerker

2014-01-01

Complex working memory (WM) span tasks have been shown to predict speech-in-noise (SIN) recognition. Studies of complex WM span tasks suggest that, rather than indexing a single cognitive process, performance on such tasks may be governed by separate cognitive subprocesses embedded within WM. Previous research has suggested that one such subprocess indexed by WM tasks is proactive interference (PI), which refers to difficulties memorizing current information because of interference from previously stored long-term memory representations for similar information. The aim of the present study was to investigate phonological PI and to examine the relationship between PI (semantic and phonological) and SIN perception. A within-subjects experimental design was used. An opportunity sample of 24 young listeners with normal hearing was recruited. Measures of resistance to, and release from, semantic and phonological PI were calculated alongside the signal-to-noise ratio required to identify 50% of keywords correctly in a SIN recognition task. The data were analyzed using t-tests and correlations. Evidence of release from and resistance to semantic interference was observed. These measures correlated significantly with SIN recognition. Limited evidence of phonological PI was observed. The results show that capacity to resist semantic PI can be used to predict SIN recognition scores in young listeners with normal hearing. On the basis of these findings, future research will focus on investigating whether tests of PI can be used in the treatment and/or rehabilitation of hearing loss. American Academy of Audiology.

Study on memories of temporal lobes and the principles of lateralization using near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Kamakura, Katsutoshi

2007-01-01

In this study we measured the variation of brain blood quantity (Oxy-Hb, Deoxy-Hb and Total-Hb) in the temporal lobes using near infrared spectroscopy (NIRS) when the tasks of the memories were presented to the subjects. The memories are classified into the short-term memory (STM) and the long-term memory (LTM) including the episodic and semantic memories. The subjects joined in this study are 11 persons who are university students including graduate students. We used the language task of letter-number sequencing, also reverse sequencing to measure STM and the task of the episodic memory to measure LTM. As a result of analysis, concerning the episodic memory, the variation of Oxy-Hb in the left temporal lobe was larger than that of Oxy-Hb in the right temporal lobe. The result might suggest that the episodic memory has a relationship with cerebral dominance concerning language area in the left temporal lobe. It seems that the episodic memory meditated with the function of language used in this study is much stored in the left temporal lobe than in the right temporal lobe. This result coincides with the principles of lateralization. The variation of Oxy-Hb in the language task of letter-number sequencing was smaller than that of Oxy-Hb in the language task of the episodic memory.

[Schizophrenia and semantic priming effects].

PubMed

Lecardeur, L; Giffard, B; Eustache, F; Dollfus, S

2006-01-01

This article is a review of studies using the semantic priming paradigm to assess the functioning of semantic memory in schizophrenic patients. Semantic priming describes the phenomenon of increasing the speed with which a string of letters (the target) is recognized as a word (lexical decision task) by presenting to the subject a semantically related word (the prime) prior to the appearance of the target word. This semantic priming is linked to both automatic and controlled processes depending on experimental conditions (stimulus onset asynchrony (SOA), percentage of related words and explicit memory instructions). Automatic process observed with short SOA, low related word percentage and instructions asking only to process the target, could be linked to the "automatic spreading activation" through the semantic network. Controlled processes involve "semantic matching" (the number of related and unrelated pairs influences the subjects decision) and "expectancy" (the prime leads the subject to generate an expectancy set of potential target to the prime). These processes can be observed whatever the SOA for the former and with long SOA for the later, but both with only high related word percentage and explicit memory instructions. Studies evaluating semantic priming effects in schizophrenia show conflicting results: schizophrenic patients can present hyperpriming (semantic priming effect is larger in patients than in controls), hypopriming (semantic priming effect is lower in patients than in controls) or equal semantic priming effects compared to control subjects. These results could be associated to a global impairment of controlled processes in schizophrenia, essentially to a dysfunction of semantic matching process. On the other hand, efficiency of semantic automatic spreading activation process is controversial. These discrepancies could be linked to the different experimental conditions used (duration of SOA, proportion of related pairs and instructions), which influence on the degree of involvement of controlled processes and therefore prevent to really assess its functioning. In addition, manipulations of the relation between prime and target (semantic distance, type of semantic relation and strength of semantic relation) seem to influence reaction times. However, the relation between prime and target (mediated priming) frequently used could not be the most relevant relation to understand the way of spreading of activation in semantic network in patients with schizophrenia. Finally, patients with formal thought disorders present particularly high priming effects relative to controls. These abnormal semantic priming effects could reflect a dysfunction of automatic spreading activation process and consequently an exaggerated diffusion of activation in the semantic network. In the future, the inclusion of different groups schizophrenic subjects could allow us to determine whether semantic memory disorders are pathognomonic or specific of a particular group of patients with schizophrenia.

Effect of episodic and working memory impairments on semantic and cognitive procedural learning at alcohol treatment entry.

PubMed

Pitel, Anne Lise; Witkowski, Thomas; Vabret, François; Guillery-Girard, Bérengère; Desgranges, Béatrice; Eustache, Francis; Beaunieux, Hélène

2007-02-01

Chronic alcoholism is known to impair the functioning of episodic and working memory, which may consequently reduce the ability to learn complex novel information. Nevertheless, semantic and cognitive procedural learning have not been properly explored at alcohol treatment entry, despite its potential clinical relevance. The goal of the present study was therefore to determine whether alcoholic patients, immediately after the weaning phase, are cognitively able to acquire complex new knowledge, given their episodic and working memory deficits. Twenty alcoholic inpatients with episodic memory and working memory deficits at alcohol treatment entry and a control group of 20 healthy subjects underwent a protocol of semantic acquisition and cognitive procedural learning. The semantic learning task consisted of the acquisition of 10 novel concepts, while subjects were administered the Tower of Toronto task to measure cognitive procedural learning. Analyses showed that although alcoholic subjects were able to acquire the category and features of the semantic concepts, albeit slowly, they presented impaired label learning. In the control group, executive functions and episodic memory predicted semantic learning in the first and second halves of the protocol, respectively. In addition to the cognitive processes involved in the learning strategies invoked by controls, alcoholic subjects seem to attempt to compensate for their impaired cognitive functions, invoking capacities of short-term passive storage. Regarding cognitive procedural learning, although the patients eventually achieved the same results as the controls, they failed to automate the procedure. Contrary to the control group, the alcoholic groups' learning performance was predicted by controlled cognitive functions throughout the protocol. At alcohol treatment entry, alcoholic patients with neuropsychological deficits have difficulty acquiring novel semantic and cognitive procedural knowledge. Compared with controls, they seem to use more costly learning strategies, which are nonetheless less efficient. These learning disabilities need to be considered when treatment requiring the acquisition of complex novel information is envisaged.

Semantic representations in the temporal pole predict false memories

PubMed Central

Chadwick, Martin J.; Anjum, Raeesa S.; Kumaran, Dharshan; Schacter, Daniel L.; Spiers, Hugo J.; Hassabis, Demis

2016-01-01

Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the “semantic hub” of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories. PMID:27551087

Semantic representations in the temporal pole predict false memories.

PubMed

Chadwick, Martin J; Anjum, Raeesa S; Kumaran, Dharshan; Schacter, Daniel L; Spiers, Hugo J; Hassabis, Demis

2016-09-06

Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the "semantic hub" of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories.

Memory: Why You're Losing It, How to Save It.

ERIC Educational Resources Information Center

Smith, Lee

1995-01-01

Describes the five types of memory: (1) semantic--what words and symbols mean; (2) implicit--how to do something such as ride a bike; (3) remote--data collected over the years; (4) working--short-term memory; and (5) episodic--recent experiences. Assesses the likelihood of each type's decaying over time. (JOW)

Can Survival Processing Enhance Story Memory? Testing the Generalizability of the Adaptive Memory Framework

ERIC Educational Resources Information Center

Seamon, John G.; Bohn, Justin M.; Coddington, Inslee E.; Ebling, Maritza C.; Grund, Ethan M.; Haring, Catherine T.; Jang, Sue-Jung; Kim, Daniel; Liong, Christopher; Paley, Frances M.; Pang, Luke K.; Siddique, Ashik H.

2012-01-01

Research from the adaptive memory framework shows that thinking about words in terms of their survival value in an incidental learning task enhances their free recall relative to other semantic encoding strategies and intentional learning (Nairne, Pandeirada, & Thompson, 2008). We found similar results. When participants used incidental…

“Going Episodic”: Collaborative Inhibition and Facilitation When Long-Married Couples Remember Together

PubMed Central

Harris, Celia B.; Barnier, Amanda J.; Sutton, John; Keil, Paul G.; Dixon, Roger A.

2017-01-01

Two complementary approaches to the study of collaborative remembering have produced contrasting results. In the experimental “collaborative recall” approach within cognitive psychology, collaborative remembering typically results in ‘collaborative inhibition’: laboratory groups recall fewer items than their estimated potential. In the cognitive ageing approach, collaborative remembering with a partner or spouse may provide cuing and support to benefit older adults’ performance on everyday memory tasks. To combine the value of experimental and cognitive ageing approaches, we tested the effects of collaborative remembering in older, long-married couples who recalled a non-personal word list and a personal semantic list of shared trips. We scored amount recalled as well as the kinds of details remembered. We found evidence for collaborative inhibition across both tasks when scored strictly as number of list items recalled. However, we found collaborative facilitation of specific episodic details on the personal semantic list, details which were not strictly required for the completion of the task. In fact, there was a trade-off between recall of specific episodic details and number of trips recalled during collaboration. We discuss these results in terms of the functions of shared remembering and what constitutes memory success, particularly for intimate groups and for older adults. PMID:28071300

A common neural substrate for language production and verbal working memory.

PubMed

Acheson, Daniel J; Hamidi, Massihullah; Binder, Jeffrey R; Postle, Bradley R

2011-06-01

Verbal working memory (VWM), the ability to maintain and manipulate representations of speech sounds over short periods, is held by some influential models to be independent from the systems responsible for language production and comprehension [e.g., Baddeley, A. D. Working memory, thought, and action. New York, NY: Oxford University Press, 2007]. We explore the alternative hypothesis that maintenance in VWM is subserved by temporary activation of the language production system [Acheson, D. J., & MacDonald, M. C. Verbal working memory and language production: Common approaches to the serial ordering of verbal information. Psychological Bulletin, 135, 50-68, 2009b]. Specifically, we hypothesized that for stimuli lacking a semantic representation (e.g., nonwords such as mun), maintenance in VWM can be achieved by cycling information back and forth between the stages of phonological encoding and articulatory planning. First, fMRI was used to identify regions associated with two different stages of language production planning: the posterior superior temporal gyrus (pSTG) for phonological encoding (critical for VWM of nonwords) and the middle temporal gyrus (MTG) for lexical-semantic retrieval (not critical for VWM of nonwords). Next, in the same subjects, these regions were targeted with repetitive transcranial magnetic stimulation (rTMS) during language production and VWM task performance. Results showed that rTMS to the pSTG, but not the MTG, increased error rates on paced reading (a language production task) and on delayed serial recall of nonwords (a test of VWM). Performance on a lexical-semantic retrieval task (picture naming), in contrast, was significantly sensitive to rTMS of the MTG. Because rTMS was guided by language production-related activity, these results provide the first causal evidence that maintenance in VWM directly depends on the long-term representations and processes used in speech production.

Reinforcement learning and episodic memory in humans and animals: an integrative framework

PubMed Central

Gershman, Samuel J.; Daw, Nathaniel D.

2018-01-01

We review the psychology and neuroscience of reinforcement learning (RL), which has witnessed significant progress in the last two decades, enabled by the comprehensive experimental study of simple learning and decision-making tasks. However, the simplicity of these tasks misses important aspects of reinforcement learning in the real world: (i) State spaces are high-dimensional, continuous, and partially observable; this implies that (ii) data are relatively sparse: indeed precisely the same situation may never be encountered twice; and also that (iii) rewards depend on long-term consequences of actions in ways that violate the classical assumptions that make RL tractable. A seemingly distinct challenge is that, cognitively, these theories have largely connected with procedural and semantic memory: how knowledge about action values or world models extracted gradually from many experiences can drive choice. This misses many aspects of memory related to traces of individual events, such as episodic memory. We suggest that these two gaps are related. In particular, the computational challenges can be dealt with, in part, by endowing RL systems with episodic memory, allowing them to (i) efficiently approximate value functions over complex state spaces, (ii) learn with very little data, and (iii) bridge long-term dependencies between actions and rewards. We review the computational theory underlying this proposal and the empirical evidence to support it. Our proposal suggests that the ubiquitous and diverse roles of memory in RL may function as part of an integrated learning system. PMID:27618944

Musical and verbal semantic memory: two distinct neural networks?

PubMed

Groussard, M; Viader, F; Hubert, V; Landeau, B; Abbas, A; Desgranges, B; Eustache, F; Platel, H

2010-02-01

Semantic memory has been investigated in numerous neuroimaging and clinical studies, most of which have used verbal or visual, but only very seldom, musical material. Clinical studies have suggested that there is a relative neural independence between verbal and musical semantic memory. In the present study, "musical semantic memory" is defined as memory for "well-known" melodies without any knowledge of the spatial or temporal circumstances of learning, while "verbal semantic memory" corresponds to general knowledge about concepts, again without any knowledge of the spatial or temporal circumstances of learning. Our aim was to compare the neural substrates of musical and verbal semantic memory by administering the same type of task in each modality. We used high-resolution PET H(2)O(15) to observe 11 young subjects performing two main tasks: (1) a musical semantic memory task, where the subjects heard the first part of familiar melodies and had to decide whether the second part they heard matched the first, and (2) a verbal semantic memory task with the same design, but where the material consisted of well-known expressions or proverbs. The musical semantic memory condition activated the superior temporal area and inferior and middle frontal areas in the left hemisphere and the inferior frontal area in the right hemisphere. The verbal semantic memory condition activated the middle temporal region in the left hemisphere and the cerebellum in the right hemisphere. We found that the verbal and musical semantic processes activated a common network extending throughout the left temporal neocortex. In addition, there was a material-dependent topographical preference within this network, with predominantly anterior activation during musical tasks and predominantly posterior activation during semantic verbal tasks. Copyright (c) 2009 Elsevier Inc. All rights reserved.

Semantic processes leading to true and false memory formation in schizophrenia.

PubMed

Paz-Alonso, Pedro M; Ghetti, Simona; Ramsay, Ian; Solomon, Marjorie; Yoon, Jong; Carter, Cameron S; Ragland, J Daniel

2013-07-01

Encoding semantic relationships between items on word lists (semantic processing) enhances true memories, but also increases memory distortions. Episodic memory impairments in schizophrenia (SZ) are strongly driven by failures to process semantic relations, but the exact nature of these relational semantic processing deficits is not well understood. Here, we used a false memory paradigm to investigate the impact of implicit and explicit semantic processing manipulations on episodic memory in SZ. Thirty SZ and 30 demographically matched healthy controls (HC) studied Deese/Roediger-McDermott (DRM) lists of semantically associated words. Half of the lists had strong implicit semantic associations and the remainder had low strength associations. Similarly, half of the lists were presented under "standard" instructions and the other half under explicit "relational processing" instructions. After study, participants performed recall and old/new recognition tests composed of targets, critical lures, and unrelated lures. HC exhibited higher true memories and better discriminability between true and false memory compared to SZ. High, versus low, associative strength increased false memory rates in both groups. However, explicit "relational processing" instructions positively improved true memory rates only in HC. Finally, true and false memory rates were associated with severity of disorganized and negative symptoms in SZ. These results suggest that reduced processing of semantic relationships during encoding in SZ may stem from an inability to implement explicit relational processing strategies rather than a fundamental deficit in the implicit activation and retrieval of word meanings from patients' semantic lexicon. Copyright © 2013 Elsevier B.V. All rights reserved.

A Diffusive-Particle Theory of Free Recall

PubMed Central

Fumarola, Francesco

2017-01-01

Diffusive models of free recall have been recently introduced in the memory literature, but their potential remains largely unexplored. In this paper, a diffusive model of short-term verbal memory is considered, in which the psychological state of the subject is encoded as the instantaneous position of a particle diffusing over a semantic graph. The model is particularly suitable for studying the dependence of free-recall observables on the semantic properties of the words to be recalled. Besides predicting some well-known experimental features (forward asymmetry, semantic clustering, word-length effect), a novel prediction is obtained on the relationship between the contiguity effect and the syllabic length of words; shorter words, by way of their wider semantic range, are predicted to be characterized by stronger forward contiguity. A fresh analysis of archival free-recall data allows to confirm this prediction. PMID:29085521

Impaired semantic knowledge underlies the reduced verbal short-term storage capacity in Alzheimer's disease.

PubMed

Peters, Frédéric; Majerus, Steve; De Baerdemaeker, Julie; Salmon, Eric; Collette, Fabienne

2009-12-01

A decrease in verbal short-term memory (STM) capacity is consistently observed in patients with Alzheimer's disease (AD). Although this impairment has been mainly attributed to attentional deficits during encoding and maintenance, the progressive deterioration of semantic knowledge in early stages of AD may also be an important determinant of poor STM performance. The aim of this study was to examine the influence of semantic knowledge on verbal short-term memory storage capacity in normal aging and in AD by exploring the impact of word imageability on STM performance. Sixteen patients suffering from mild AD, 16 healthy elderly subjects and 16 young subjects performed an immediate serial recall task using word lists containing high or low imageability words. All participant groups recalled more high imageability words than low imageability words, but the effect of word imageability on verbal STM was greater in AD patients than in both the young and the elderly control groups. More precisely, AD patients showed a marked decrease in STM performance when presented with lists of low imageability words, whereas recall of high imageability words was relatively well preserved. Furthermore, AD patients displayed an abnormal proportion of phonological errors in the low imageability condition. Overall, these results indicate that the support of semantic knowledge on STM performance was impaired for lists of low imageability words in AD patients. More generally, these findings suggest that the deterioration of semantic knowledge is partly responsible for the poor verbal short-term storage capacity observed in AD.

Vector Symbolic Spiking Neural Network Model of Hippocampal Subarea CA1 Novelty Detection Functionality.

PubMed

Agerskov, Claus

2016-04-01

A neural network model is presented of novelty detection in the CA1 subdomain of the hippocampal formation from the perspective of information flow. This computational model is restricted on several levels by both anatomical information about hippocampal circuitry and behavioral data from studies done in rats. Several studies report that the CA1 area broadcasts a generalized novelty signal in response to changes in the environment. Using the neural engineering framework developed by Eliasmith et al., a spiking neural network architecture is created that is able to compare high-dimensional vectors, symbolizing semantic information, according to the semantic pointer hypothesis. This model then computes the similarity between the vectors, as both direct inputs and a recalled memory from a long-term memory network by performing the dot-product operation in a novelty neural network architecture. The developed CA1 model agrees with available neuroanatomical data, as well as the presented behavioral data, and so it is a biologically realistic model of novelty detection in the hippocampus, which can provide a feasible explanation for experimentally observed dynamics.

Considering the role of semantic memory in episodic future thinking: evidence from semantic dementia.

PubMed

Irish, Muireann; Addis, Donna Rose; Hodges, John R; Piguet, Olivier

2012-07-01

Semantic dementia is a progressive neurodegenerative condition characterized by the profound and amodal loss of semantic memory in the context of relatively preserved episodic memory. In contrast, patients with Alzheimer's disease typically display impairments in episodic memory, but with semantic deficits of a much lesser magnitude than in semantic dementia. Our understanding of episodic memory retrieval in these cohorts has greatly increased over the last decade, however, we know relatively little regarding the ability of these patients to imagine and describe possible future events, and whether episodic future thinking is mediated by divergent neural substrates contingent on dementia subtype. Here, we explored episodic future thinking in patients with semantic dementia (n=11) and Alzheimer's disease (n=11), in comparison with healthy control participants (n=10). Participants completed a battery of tests designed to probe episodic and semantic thinking across past and future conditions, as well as standardized tests of episodic and semantic memory. Further, all participants underwent magnetic resonance imaging. Despite their relatively intact episodic retrieval for recent past events, the semantic dementia cohort showed significant impairments for episodic future thinking. In contrast, the group with Alzheimer's disease showed parallel deficits across past and future episodic conditions. Voxel-based morphometry analyses confirmed that atrophy in the left inferior temporal gyrus and bilateral temporal poles, regions strongly implicated in semantic memory, correlated significantly with deficits in episodic future thinking in semantic dementia. Conversely, episodic future thinking performance in Alzheimer's disease correlated with atrophy in regions associated with episodic memory, namely the posterior cingulate, parahippocampal gyrus and frontal pole. These distinct neuroanatomical substrates contingent on dementia group were further qualified by correlational analyses that confirmed the relation between semantic memory deficits and episodic future thinking in semantic dementia, in contrast with the role of episodic memory deficits and episodic future thinking in Alzheimer's disease. Our findings demonstrate that semantic knowledge is critical for the construction of novel future events, providing the necessary scaffolding into which episodic details can be integrated. Further research is necessary to elucidate the precise contribution of semantic memory to future thinking, and to explore how deficits in self-projection manifest on behavioural and social levels in different dementia subtypes.

Mapping the Structure of Semantic Memory

ERIC Educational Resources Information Center

Morais, Ana Sofia; Olsson, Henrik; Schooler, Lael J.

2013-01-01

Aggregating snippets from the semantic memories of many individuals may not yield a good map of an individual's semantic memory. The authors analyze the structure of semantic networks that they sampled from individuals through a new snowball sampling paradigm during approximately 6 weeks of 1-hr daily sessions. The semantic networks of individuals…

On the adaptive flexibility of evaluative priming.

PubMed

Fiedler, Klaus; Bluemke, Matthias; Unkelbach, Christian

2011-05-01

If priming effects serve an adaptive function, they have to be both robust and flexible. In four experiments, we demonstrated regular evaluative-priming effects for relatively long stimulus-onset asynchronies, which can, however, be eliminated or reversed strategically. When participants responded to both primes and targets, rather than only to targets, the standard congruity effect disappeared. In Experiments 1a-1c, this result was regularly obtained, independently of the prime response (valence or gender classification) and the response mode (pronunciation or keystroke). In Experiment 2, we showed that once the default congruity effect was eliminated, strategic-priming effects reflected the statistical contingency between prime valence and target valence. Positive contingencies produced congruity, whereas negative contingencies produced equally strong incongruity effects. Altogether, these findings are consistent with an adaptive-cognitive perspective, which highlights the role of flexible strategic processes in working memory as opposed to fixed structures in semantic long-term memory or in the sensorimotor system.

Semantic memory and depressive symptoms in patients with subjective cognitive decline, mild cognitive impairment, and Alzheimer's disease.

PubMed

Lehrner, J; Coutinho, G; Mattos, P; Moser, D; Pflüger, M; Gleiss, A; Auff, E; Dal-Bianco, P; Pusswald, G; Stögmann, E

2017-07-01

Semantic memory may be impaired in clinically recognized states of cognitive impairment. We investigated the relationship between semantic memory and depressive symptoms (DS) in patients with cognitive impairment. 323 cognitively healthy controls and 848 patients with subjective cognitive decline (SCD), mild cognitive impairment (MCI), and Alzheimer's disease (AD) dementia were included. Semantic knowledge for famous faces, world capitals, and word vocabulary was investigated. Compared to healthy controls, we found a statistically significant difference of semantic knowledge in the MCI groups and the AD group, respectively. Results of the SCD group were mixed. However, two of the three semantic memory measures (world capitals and word vocabulary) showed a significant association with DS. We found a difference in semantic memory performance in MCI and AD as well as an association with DS. Results suggest that the difference in semantic memory is due to a storage loss rather than to a retrieval problem.

Episodic and Semantic Aspects of Memory for Prose.

ERIC Educational Resources Information Center

Dooling, D. James

This report describes research on Bartlett's theory of constructive memory. In experiment one, schematic retention is related to Tulving's distinction between episodic and semantic memory. With the passage of time, memory for prose reflects decreasing output from episodic memory and increasing output from semantic memory. In experiment two,…

Right temporal cortical hypertrophy in resilience to trauma: an MRI study

PubMed Central

Nilsen, André Sevenius; Hilland, Eva; Kogstad, Norunn; Heir, Trond; Hauff, Edvard; Lien, Lars; Endestad, Tor

2016-01-01

Background In studies employing physiological measures such as magnetic resonance imaging (MRI), it is often hard to distinguish what constitutes risk-resilience factors to posttraumatic stress disorder (PTSD) following trauma exposure and what the effects of trauma exposure and PTSD are. Objective We aimed to investigate whether there were observable morphological differences in cortical and sub-cortical regions of the brain, 7–8 years after a single potentially traumatic event. Methods Twenty-four participants, who all directly experienced the 2004 Indian Ocean Tsunami, and 25 controls, underwent structural MRI using a 3T scanner. We generated cortical thickness maps and parcellated sub-cortical volumes for analysis. Results We observed greater cortical thickness for the trauma-exposed participants relative to controls, in a right lateralized temporal lobe region including anterior fusiform gyrus, and superior, middle, and inferior temporal gyrus. Conclusions We observed greater thickness in the right temporal lobe which might indicate that the region could be implicated in resilience to the long-term effects of a traumatic event. We hypothesize this is due to altered emotional semantic memory processing. However, several methodological and confounding issues warrant caution in interpretation of the results. Highlights of the article Following a traumatic event, most people do not develop long-lasting trauma-related symptoms.In a group who experienced a traumatic event 8 years prior, but showed low levels of trauma-related symptoms, we observed increased cortical thickness in the right temporal lobe.The right temporal lobe is implicated in emotional semantic memory processing, and thus might be associated with resilience to the long-term effects of a traumatic event. PMID:27473521

Semantic and Syntactic Interference in Sentence Comprehension: A Comparison of Working Memory Models

PubMed Central

Tan, Yingying; Martin, Randi C.; Van Dyke, Julie A.

2017-01-01

This study investigated the nature of the underlying working memory system supporting sentence processing through examining individual differences in sensitivity to retrieval interference effects during sentence comprehension. Interference effects occur when readers incorrectly retrieve sentence constituents which are similar to those required during integrative processes. We examined interference arising from a partial match between distracting constituents and syntactic and semantic cues, and related these interference effects to performance on working memory, short-term memory (STM), vocabulary, and executive function tasks. For online sentence comprehension, as measured by self-paced reading, the magnitude of individuals' syntactic interference effects was predicted by general WM capacity and the relation remained significant when partialling out vocabulary, indicating that the effects were not due to verbal knowledge. For offline sentence comprehension, as measured by responses to comprehension questions, both general WM capacity and vocabulary knowledge interacted with semantic interference for comprehension accuracy, suggesting that both general WM capacity and the quality of semantic representations played a role in determining how well interference was resolved offline. For comprehension question reaction times, a measure of semantic STM capacity interacted with semantic but not syntactic interference. However, a measure of phonological capacity (digit span) and a general measure of resistance to response interference (Stroop effect) did not predict individuals' interference resolution abilities in either online or offline sentence comprehension. The results are discussed in relation to the multiple capacities account of working memory (e.g., Martin and Romani, 1994; Martin and He, 2004), and the cue-based retrieval parsing approach (e.g., Lewis et al., 2006; Van Dyke et al., 2014). While neither approach was fully supported, a possible means of reconciling the two approaches and directions for future research are proposed. PMID:28261133

Neuropsychological Testing in Interventional Cardiology Staff after Long-Term Exposure to Ionizing Radiation.

PubMed

Marazziti, Donatella; Tomaiuolo, Francesco; Dell'Osso, Liliana; Demi, Virginia; Campana, Serena; Piccaluga, Emanuela; Guagliumi, Giulio; Conversano, Ciro; Baroni, Stefano; Andreassi, Maria Grazia; Picano, Eugenio

2015-10-01

This study aimed at comparing neuropsychological test scores in 83 cardiologists and nurses (exposed group, EG) working in the cardiac catheterization laboratory, and 83 control participants (non exposed group, nEG), to explore possible cognitive impairments. The neuropsychological assessment was carried out by means of a battery called "Esame Neuropsicologico Breve." EG participants showed significantly lower scores on the delayed recall, visual short-term memory, and semantic lexical access ability than the nEG ones. No dose response could be detected. EG participants showed lower memory and verbal fluency performances, as compared with nEG. These reduced skills suggest alterations of some left hemisphere structures that are more exposed to IR in interventional cardiology staff. On the basis of these findings, therefore, head protection would be a mandatory good practice to reduce effects of head exposure to ionizing radiation among invasive cardiology personnel (and among other exposed professionals).

Past, present, and prospects: Reflections 40 years on from the selective impairment of semantic memory (Warrington, 1975).

PubMed

McCarthy, Rosaleen A; Warrington, Elizabeth K

2016-10-01

We summarize the main findings and conclusions of Warrington's (1975) paper, The Selective Impairment of Semantic memory, a neuropsychological paper that described three cases with degenerative neurological conditions [Warrington, E. K. (1975). The selective impairment of semantic memory. The Quarterly Journal of Experimental Psychology, 27, 635-657]. We consider the developments that have followed from its publication and give a selective overview of the field in 2014. The initial impact of the paper was on neuropsychological investigations of semantic loss followed some 14 years later by the identification of Semantic Dementia (the condition shown by the original cases) as a distinctive form of degenerative disease with unique clinical and pathological characteristics. We discuss the distinction between disorders of semantic storage and refractory semantic access, the evidence for category- and modality-specific impairments of semantics, and the light that has been shed on the structure and organization of semantic memory. Finally we consider the relationship between semantic memory and the skills of reading and writing, phonological processing, and autobiographical memory.

The Latent Structure of Memory: A Confirmatory Factor-Analytic Study of Memory Distinctions.

ERIC Educational Resources Information Center

Herrman, Douglas J.; Schooler, Carmi; Caplan, Leslie J.; Lipman, Paula Darby; Grafman, Jordan; Schoenbach, Carrie; Schwab, Karen; Johnson, Marnie L.

2001-01-01

Used confirmatory factor analysis to study the nature of memory distinctions underlying the performance of two samples of Vietnam veterans. One sample (n=96) had received head injuries resulting in relatively small lesions; the other (n=85) had not. A four-component model with verbal-episodic, visual-episodic, semantic, and short-term memory…

A Probabilistic Model of Social Working Memory for Information Retrieval in Social Interactions.

PubMed

Li, Liyuan; Xu, Qianli; Gan, Tian; Tan, Cheston; Lim, Joo-Hwee

2018-05-01

Social working memory (SWM) plays an important role in navigating social interactions. Inspired by studies in psychology, neuroscience, cognitive science, and machine learning, we propose a probabilistic model of SWM to mimic human social intelligence for personal information retrieval (IR) in social interactions. First, we establish a semantic hierarchy as social long-term memory to encode personal information. Next, we propose a semantic Bayesian network as the SWM, which integrates the cognitive functions of accessibility and self-regulation. One subgraphical model implements the accessibility function to learn the social consensus about IR-based on social information concept, clustering, social context, and similarity between persons. Beyond accessibility, one more layer is added to simulate the function of self-regulation to perform the personal adaptation to the consensus based on human personality. Two learning algorithms are proposed to train the probabilistic SWM model on a raw dataset of high uncertainty and incompleteness. One is an efficient learning algorithm of Newton's method, and the other is a genetic algorithm. Systematic evaluations show that the proposed SWM model is able to learn human social intelligence effectively and outperforms the baseline Bayesian cognitive model. Toward real-world applications, we implement our model on Google Glass as a wearable assistant for social interaction.

Task context and organization in free recall

PubMed Central

Polyn, Sean M.; Norman, Kenneth A.; Kahana, Michael J.

2009-01-01

Prior work on organization in free recall has focused on the ways in which semantic and temporal information determine the order in which material is retrieved from memory. Tulving’s theory of ecphory suggests that these organizational effects arise from the interaction of a retrieval cue with the contents of memory. Using the continual-distraction free-recall paradigm (Bjork & Whitten, 1974) to minimize retrieval during the study period, we show that encoding task context can organize recall, suggesting that task-related information is part of the retrieval cue. We interpret these results in terms of the Context Maintenance and Retrieval model (CMR; Polyn, Norman, & Kahana, in press), in which an internal contextual representation, containing semantic, temporal, and source-related information, serves as the retrieval cue and organizes the retrieval of information from memory. We discuss these results in terms of the guided activation theory (Miller & Cohen, 2001) of the role of prefrontal cortex in task performance, as well as the rich neuropsychological literature implicating prefrontal cortex in memory search (e.g, Schacter, 1987). PMID:19524086

A SEMantic and EPisodic Memory Test (SEMEP) Developed within the Embodied Cognition Framework: Application to Normal Aging, Alzheimer's Disease and Semantic Dementia.

PubMed

Vallet, Guillaume T; Hudon, Carol; Bier, Nathalie; Macoir, Joël; Versace, Rémy; Simard, Martine

2017-01-01

Embodiment has highlighted the importance of sensory-motor components in cognition. Perception and memory are thus very tightly bound together, and episodic and semantic memories should rely on the same grounded memory traces. Reduced perception should then directly reduce the ability to encode and retrieve an episodic memory, as in normal aging. Multimodal integration deficits, as in Alzheimer's disease, should lead to more severe episodic memory impairment. The present study introduces a new memory test developed to take into account these assumptions. The SEMEP (SEMantic-Episodic) memory test proposes to assess conjointly semantic and episodic knowledge across multiple tasks: semantic matching, naming, free recall, and recognition. The performance of young adults is compared to healthy elderly adults (HE), patients with Alzheimer's disease (AD), and patients with semantic dementia (SD). The results show specific patterns of performance between the groups. HE commit memory errors only for presented but not to be remembered items. AD patients present the worst episodic memory performance associated with intrusion errors (recall or recognition of items never presented). They were the only group to not benefit from a visual isolation (addition of a yellow background), a method known to increase the distinctiveness of the memory traces. Finally, SD patients suffer from the most severe semantic impairment. To conclude, confusion errors are common across all the elderly groups, whereas AD was the only group to exhibit regular intrusion errors and SD patients to show severe semantic impairment.

Developmental amnesia: a new pattern of dissociation with intact episodic memory.

PubMed

Temple, Christine M; Richardson, Paul

2004-01-01

A case of developmental amnesia is reported for a child, CL, of normal intelligence, who has intact episodic memory but impaired semantic memory for both semantic knowledge of facts and semantic knowledge of words, including general world knowledge, knowledge of word meanings and superordinate knowledge of words. In contrast to the deficits in semantic memory, there are no impairments in episodic memory for verbal or visual material, assessed by recall or recognition. Lexical decision was also intact, indicating impairment in semantic knowledge of vocabulary rather than absence of lexical representations. The case forms a double dissociation to the cases of Vargha-Khadem et al. [Science 277 (1997) 376; Episodic memory: new directions in research (2002) 153]; Gadian et al. [Brain 123 (2000) 499] for whom semantic memory was intact but episodic memory was impaired. This double dissociation suggests that semantic memory and episodic memory have the capacity to develop separately and supports models of modularity within memory development and a functional architecture for the developmental disorders within which there is residual normality rather than pervasive abnormality. Knowledge of arithmetical facts is also spared for CL, consistent with adult studies arguing for numeracy knowledge distinct from other semantics. Reading was characterised by difficulty with irregular words and homophones but intact reading of nonwords. CL has surface dyslexia with poor lexico-semantic reading skills but good phonological reading skills. The case was identified following screening from a population of normal schoolchildren suggesting that developmental amnesias may be more pervasive than has been recognised previously.

Differential Medial Temporal Lobe and Parietal Cortical Contributions to Real-world Autobiographical Episodic and Autobiographical Semantic Memory.

PubMed

Brown, Thackery I; Rissman, Jesse; Chow, Tiffany E; Uncapher, Melina R; Wagner, Anthony D

2018-04-18

Autobiographical remembering can depend on two forms of memory: episodic (event) memory and autobiographical semantic memory (remembering personally relevant semantic knowledge, independent of recalling a specific experience). There is debate about the degree to which the neural signals that support episodic recollection relate to or build upon autobiographical semantic remembering. Pooling data from two fMRI studies of memory for real-world personal events, we investigated whether medial temporal lobe (MTL) and parietal subregions contribute to autobiographical episodic and semantic remembering. During scanning, participants made memory judgments about photograph sequences depicting past events from their life or from others' lives, and indicated whether memory was based on episodic or semantic knowledge. Results revealed several distinct functional patterns: activity in most MTL subregions was selectively associated with autobiographical episodic memory; the hippocampal tail, superior parietal lobule, and intraparietal sulcus were similarly engaged when memory was based on retrieval of an autobiographical episode or autobiographical semantic knowledge; and angular gyrus demonstrated a graded pattern, with activity declining from autobiographical recollection to autobiographical semantic remembering to correct rejections of novel events. Collectively, our data offer insights into MTL and parietal cortex functional organization, and elucidate circuitry that supports different forms of real-world autobiographical memory.

Verbal and non-verbal semantic impairment: From fluent primary progressive aphasia to semantic dementia

PubMed Central

Senaha, Mirna Lie Hosogi; Caramelli, Paulo; Porto, Claudia Sellitto; Nitrini, Ricardo

2007-01-01

Selective disturbances of semantic memory have attracted the interest of many investigators and the question of the existence of single or multiple semantic systems remains a very controversial theme in the literature. Objectives To discuss the question of multiple semantic systems based on a longitudinal study of a patient who presented semantic dementia from fluent primary progressive aphasia. Methods A 66 year-old woman with selective impairment of semantic memory was examined on two occasions, undergoing neuropsychological and language evaluations, the results of which were compared to those of three paired control individuals. Results In the first evaluation, physical examination was normal and the score on the Mini-Mental State Examination was 26. Language evaluation revealed fluent speech, anomia, disturbance in word comprehension, preservation of the syntactic and phonological aspects of the language, besides surface dyslexia and dysgraphia. Autobiographical and episodic memories were relatively preserved. In semantic memory tests, the following dissociation was found: disturbance of verbal semantic memory with preservation of non-verbal semantic memory. Magnetic resonance of the brain revealed marked atrophy of the left anterior temporal lobe. After 14 months, the difficulties in verbal semantic memory had become more severe and the semantic disturbance, limited initially to the linguistic sphere, had worsened to involve non-verbal domains. Conclusions Given the dissociation found in the first examination, we believe there is sufficient clinical evidence to refute the existence of a unitary semantic system. PMID:29213389

Retrograde amnesia in patients with hippocampal, medial temporal, temporal lobe, or frontal pathology.

PubMed

Bright, Peter; Buckman, Joseph; Fradera, Alex; Yoshimasu, Haruo; Colchester, Alan C F; Kopelman, Michael D

2006-01-01

There is considerable controversy concerning the theoretical basis of retrograde amnesia (R.A.). In the present paper, we compare medial temporal, medial plus lateral temporal, and frontal lesion patients on a new autobiographical memory task and measures of the more semantic aspects of memory (famous faces and news events). Only those patients with damage extending beyond the medial temporal cortex into the lateral temporal regions showed severe impairment on free recall remote memory tasks, and this held for both the autobiographical and the more semantic memory tests. However, on t-test analysis, the medial temporal group was impaired in retrieving recent autobiographical memories. Within the medial temporal group, those patients who had combined hippocampal and parahippocampal atrophy (H+) on quantified MRI performed somewhat worse on the semantic tasks than those with atrophy confined to the hippocampi (H-), but scores were very similar on autobiographical episodic recall. Correlational analyses with regional MRI volumes showed that lateral temporal volume was correlated significantly with performance on all three retrograde amnesia tests. The findings are discussed in terms of consolidation, reconsolidation, and multiple trace theory: We suggest that a widely distributed network of regions underlies the retrieval of past memories, and that the extent of lateral temporal damage appears to be critical to the emergence of a severe remote memory impairment.

The ERP correlates of self-knowledge: Are assessments of one's past, present, and future traits closer to semantic or episodic memory?

PubMed

Tanguay, Annick N; Benton, Lauren; Romio, Lorenza; Sievers, Carolin; Davidson, Patrick S R; Renoult, Louis

2018-02-01

Self-knowledge concerns one's own preferences and personality. It pertains to the self (similar to episodic memory), yet does not concern events. It is factual (like semantic memory), but also idiosyncratic. For these reasons, it is unclear where self-knowledge might fall on a continuum in relation to semantic and episodic memory. In this study, we aimed to compare the event-related potential (ERP) correlates of self-knowledge to those of semantic and episodic memory, using N400 and Late Positive Component (LPC) as proxies for semantic and episodic processing, respectively. We considered an additional factor: time perspective. Temporally distant selves have been suggested to be more semantic compared to the present self, but thinking about one's past and future selves may also engage episodic memory. Twenty-eight adults answered whether traits (e.g., persistent) were true of most people holding an occupation (e.g., soldiers; semantic memory condition), or true of themselves 5 years ago, in the present, or 5 years from now (past, present, and future self-knowledge conditions). The study ended with an episodic recognition memory task for previously seen traits. Present self-knowledge produced mean LPC amplitudes at posterior parietal sites that fell between semantic and episodic memory. Mean LPC amplitudes for past and future self-knowledge were greater than for semantic memory, and not significantly different from episodic memory. Mean N400 amplitudes for the self-knowledge conditions were smaller than for semantic memory at sagittal sites. However, this N400 effect was not separable from a preceding P200 effect at these same electrode sites. This P200 effect can be interpreted as reflecting the greater emotional salience of self as compared to general knowledge, which may have facilitated semantic processing. Overall, our findings are consistent with a distinction between knowledge of others and self-knowledge, but the closeness of self-knowledge's neural correlates to either semantic or episodic memory appears to depend to some extent on time perspective. Copyright © 2017 Elsevier Ltd. All rights reserved.

Recall from Semantic and Episodic Memory.

ERIC Educational Resources Information Center

Gillund, Gary; Perlmutter, Marion

Although research in episodic recall memory, comparing younger and older adults, favors the younger adults, findings in semantic memory research are less consistent. To examine age differences in semantic and episodic memory recall, 72 young adults (mean age, 20.8) and 72 older adults (mean age 71) completed three memory tests under varied…

Focal retrograde amnesia and the episodic-semantic distinction.

PubMed

Wheeler, M A; McMillan, C T

2001-03-01

This article reports a review of focal retrograde amnesia (FRA), or the phenomenon of organically based severe memory loss restricted to retrograde, or pretraumatic, memory. Cases of FRA are classified according to the type of memory loss: episodic, semantic, or both. A few different clusters of the disorder were identified. Lesions to either the anterior temporal lobes or the posterior/visual cortex can result in an FRA that devastates retrograde episodic memory, while having smaller effects on semantic memory. A number of left-hemisphere patients have FRA confined to semantic memory. There are several additional examples of FRA following minor cerebral trauma that disrupts either episodic memory alone or both episodic and semantic memory that are not accompanied by evidence of structural brain lesions. We discuss these different profiles of FRA and their implications for the understanding of memory retrieval.

Virtual reality-based prospective memory training program for people with acquired brain injury.

PubMed

Yip, Ben C B; Man, David W K

2013-01-01

Acquired brain injuries (ABI) may display cognitive impairments and lead to long-term disabilities including prospective memory (PM) failure. Prospective memory serves to remember to execute an intended action in the future. PM problems would be a challenge to an ABI patient's successful community reintegration. While retrospective memory (RM) has been extensively studied, treatment programs for prospective memory are rarely reported. The development of a treatment program for PM, which is considered timely, can be cost-effective and appropriate to the patient's environment. A 12-session virtual reality (VR)-based cognitive rehabilitation program was developed using everyday PM activities as training content. 37 subjects were recruited to participate in a pretest-posttest control experimental study to evaluate its treatment effectiveness. Results suggest that significantly better changes were seen in both VR-based and real-life PM outcome measures, related cognitive attributes such as frontal lobe functions and semantic fluency. VR-based training may be well accepted by ABI patients as encouraging improvement has been shown. Large-scale studies of a virtual reality-based prospective memory (VRPM) training program are indicated.

Long-term priming of the meanings of ambiguous words

ERIC Educational Resources Information Center

Rodd, Jennifer M.; Lopez Cutrin, Belen; Kirsch, Hannah; Millar, Allesandra; Davis, Matthew H.

2013-01-01

Comprehension of semantically ambiguous words (e.g., "bark") is strongly influenced by the relative frequencies of their meanings, such that listeners are biased towards retrieving the most frequent meaning. These biases are often assumed to reflect a highly stable property of an individual's long-term lexical-semantic representations. We present…

The self-imagination effect: benefits of a self-referential encoding strategy on cued recall in memory-impaired individuals with neurological damage.

PubMed

Grilli, Matthew D; Glisky, Elizabeth L

2011-09-01

Knowledge of oneself is preserved in many memory-impaired individuals with neurological damage. Therefore, cognitive strategies that capitalize on mechanisms related to the self may be particularly effective at enhancing memory in this population. The present study investigated the effect of "self-imagining," imagining an event from a personal perspective, on short and long delayed cued recall in memory-impaired individuals with neurological damage. Sixteen patients intentionally encoded word pairs under four separate conditions: visual imagery, semantic elaboration, other person imagining, and self-imagining. The results revealed that self-imagining led to better performance than other-imagining, semantic elaboration, and visual imagery. Furthermore, the "self-imagination effect" (SIE) was preserved after a 30-min delay and was independent of memory functioning. These findings indicate that self-imagining provides a mnemonic advantage in brain-injured individuals, even those with relatively poor memory functioning, and suggest that self-imagining may tap into mnemonic mechanisms related to the self.

"Truth be told" - Semantic memory as the scaffold for veridical communication.

PubMed

Hayes, Brett K; Ramanan, Siddharth; Irish, Muireann

2018-01-01

Theoretical accounts placing episodic memory as central to constructive and communicative functions neglect the role of semantic memory. We argue that the decontextualized nature of semantic schemas largely supersedes the computational bottleneck and error-prone nature of episodic memory. Rather, neuroimaging and neuropsychological evidence of episodic-semantic interactions suggest that an integrative framework more accurately captures the mechanisms underpinning social communication.

Neural Dynamics Associated with Semantic and Episodic Memory for Faces: Evidence from Multiple Frequency Bands

ERIC Educational Resources Information Center

Zion-Golumbic, Elana; Kutas, Marta; Bentin, Shlomo

2010-01-01

Prior semantic knowledge facilitates episodic recognition memory for faces. To examine the neural manifestation of the interplay between semantic and episodic memory, we investigated neuroelectric dynamics during the creation (study) and the retrieval (test) of episodic memories for famous and nonfamous faces. Episodic memory effects were evident…

The Pivotal Role of Semantic Memory in Remembering the Past and Imagining the Future

PubMed Central

Irish, Muireann; Piguet, Olivier

2013-01-01

Episodic memory refers to a complex and multifaceted process which enables the retrieval of richly detailed evocative memories from the past. In contrast, semantic memory is conceptualized as the retrieval of general conceptual knowledge divested of a specific spatiotemporal context. The neural substrates of the episodic and semantic memory systems have been dissociated in healthy individuals during functional imaging studies, and in clinical cohorts, leading to the prevailing view that episodic and semantic memory represent functionally distinct systems subtended by discrete neurobiological substrates. Importantly, however, converging evidence focusing on widespread neural networks now points to significant overlap between those regions essential for retrieval of autobiographical memories, episodic learning, and semantic processing. Here we review recent advances in episodic memory research focusing on neurodegenerative populations which has proved revelatory for our understanding of the complex interplay between episodic and semantic memory. Whereas episodic memory research has traditionally focused on retrieval of autobiographical events from the past, we also include evidence from the recent paradigm shift in which episodic memory is viewed as an adaptive and constructive process which facilitates the imagining of possible events in the future. We examine the available evidence which converges to highlight the pivotal role of semantic memory in providing schemas and meaning whether one is engaged in autobiographical retrieval for the past, or indeed, is endeavoring to construct a plausible scenario of an event in the future. It therefore seems plausible to contend that semantic processing may underlie most, if not all, forms of episodic memory, irrespective of temporal condition. PMID:23565081

Effects of saccadic bilateral eye movements on episodic and semantic autobiographical memory fluency.

PubMed

Parker, Andrew; Parkin, Adam; Dagnall, Neil

2013-01-01

Performing a sequence of fast saccadic horizontal eye movements has been shown to facilitate performance on a range of cognitive tasks, including the retrieval of episodic memories. One explanation for these effects is based on the hypothesis that saccadic eye movements increase hemispheric interaction, and that such interactions are important for particular types of memory. The aim of the current research was to assess the effect of horizontal saccadic eye movements on the retrieval of both episodic autobiographical memory (event/incident based memory) and semantic autobiographical memory (fact based memory) over recent and more distant time periods. It was found that saccadic eye movements facilitated the retrieval of episodic autobiographical memories (over all time periods) but not semantic autobiographical memories. In addition, eye movements did not enhance the retrieval of non-autobiographical semantic memory. This finding illustrates a dissociation between the episodic and semantic characteristics of personal memory and is considered within the context of hemispheric contributions to episodic memory performance.

Effects of Saccadic Bilateral Eye Movements on Episodic and Semantic Autobiographical Memory Fluency

PubMed Central

Parker, Andrew; Parkin, Adam; Dagnall, Neil

2013-01-01

Performing a sequence of fast saccadic horizontal eye movements has been shown to facilitate performance on a range of cognitive tasks, including the retrieval of episodic memories. One explanation for these effects is based on the hypothesis that saccadic eye movements increase hemispheric interaction, and that such interactions are important for particular types of memory. The aim of the current research was to assess the effect of horizontal saccadic eye movements on the retrieval of both episodic autobiographical memory (event/incident based memory) and semantic autobiographical memory (fact based memory) over recent and more distant time periods. It was found that saccadic eye movements facilitated the retrieval of episodic autobiographical memories (over all time periods) but not semantic autobiographical memories. In addition, eye movements did not enhance the retrieval of non-autobiographical semantic memory. This finding illustrates a dissociation between the episodic and semantic characteristics of personal memory and is considered within the context of hemispheric contributions to episodic memory performance. PMID:24133435

Attention, Working Memory, and Grammaticality Judgment in Typical Young Adults

ERIC Educational Resources Information Center

Smith, Pamela A.

2011-01-01

Purpose: To examine resource allocation and sentence processing, this study examined the effects of auditory distraction on grammaticality judgment (GJ) of sentences varied by semantics (reversibility) and short-term memory requirements. Method: Experiment 1: Typical young adult females (N = 60) completed a whole-sentence GJ task in distraction…

Extent and neural basis of semantic memory impairment in mild cognitive impairment.

PubMed

Barbeau, Emmanuel J; Didic, Mira; Joubert, Sven; Guedj, Eric; Koric, Lejla; Felician, Olivier; Ranjeva, Jean-Philippe; Cozzone, Patrick; Ceccaldi, Mathieu

2012-01-01

An increasing number of studies indicate that semantic memory is impaired in mild cognitive impairment (MCI). However, the extent and the neural basis of this impairment remain unknown. The aim of the present study was: 1) to evaluate whether all or only a subset of semantic domains are impaired in MCI patients; and 2) to assess the neural substrate of the semantic impairment in MCI patients using voxel-based analysis of MR grey matter density and SPECT perfusion. 29 predominantly amnestic MCI patients and 29 matched control subjects participated in this study. All subjects underwent a full neuropsychological assessment, along with a battery of five tests evaluating different domains of semantic memory. A semantic memory composite Z-score was established on the basis of this battery and was correlated with MRI grey matter density and SPECT perfusion measures. MCI patients were found to have significantly impaired performance across all semantic tasks, in addition to their anterograde memory deficit. Moreover, no temporal gradient was found for famous faces or famous public events and knowledge for the most remote decades was also impaired. Neuroimaging analyses revealed correlations between semantic knowledge and perirhinal/entorhinal areas as well as the anterior hippocampus. Therefore, the deficits in the realm of semantic memory in patients with MCI is more widespread than previously thought and related to dysfunction of brain areas beyond the limbic-diencephalic system involved in episodic memory. The severity of the semantic impairment may indicate a decline of semantic memory that began many years before the patients first consulted.

Cue self-relevance affects autobiographical memory specificity in individuals with a history of major depression

PubMed Central

Crane, Catherine; Barnhofer, Thorsten; Williams, J. Mark G.

2007-01-01

Previously depressed and never-depressed individuals identified personal characteristics (self-guides) defining their ideal, ought, and feared selves. One week later they completed the autobiographical memory test (AMT). For each participant the number of AMT cues that reflected self-guide content was determined to produce an index of AMT cue self-relevance. Individuals who had never been depressed showed no significant relationship between cue self-relevance and specificity. In contrast, in previously depressed participants there was a highly significant negative correlation between cue self-relevance and specificity—the greater the number of AMT cues that reflected self-guide content, the fewer specific memories participants recalled. It is suggested that in individuals with a history of depression, cues reflecting self-guide content are more likely to prompt a shift to processing of information within the long-term self (Conway, Singer, & Tagini, 2004), increasing the likelihood that self-related semantic information will be provided in response to cues on the autobiographical memory test. PMID:17454667

Cue self-relevance affects autobiographical memory specificity in individuals with a history of major depression.

PubMed

Crane, Catherine; Barnhofer, Thorsten; Mark, J; Williams, G

2007-04-01

Previously depressed and never-depressed individuals identified personal characteristics (self-guides) defining their ideal, ought, and feared selves. One week later they completed the autobiographical memory test (AMT). For each participant the number of AMT cues that reflected self-guide content was determined to produce an index of AMT cue self-relevance. Individuals who had never been depressed showed no significant relationship between cue self-relevance and specificity. In contrast, in previously depressed participants there was a highly significant negative correlation between cue self-relevance and specificity--the greater the number of AMT cues that reflected self-guide content, the fewer specific memories participants recalled. It is suggested that in individuals with a history of depression, cues reflecting self-guide content are more likely to prompt a shift to processing of information within the long-term self (Conway, Singer, & Tagini, 2004), increasing the likelihood that self-related semantic information will be provided in response to cues on the autobiographical memory test.

Episodic and Semantic Memory Contribute to Familiar and Novel Episodic Future Thinking.

PubMed

Wang, Tong; Yue, Tong; Huang, Xi Ting

2016-01-01

Increasing evidence indicates that episodic future thinking (EFT) relies on both episodic and semantic memory; however, event familiarity may importantly affect the extent to which episodic and semantic memory contribute to EFT. To test this possibility, two behavioral experiments were conducted. In Experiment 1, we directly compared the proportion of episodic and semantic memory used in an EFT task. The results indicated that more episodic memory was used when imagining familiar future events compared with novel future events. Conversely, significantly more semantic memory was used when imagining novel events compared with familiar events. Experiment 2 aimed to verify the results of Experiment 1. In Experiment 2, we found that familiarity moderated the effect of priming the episodic memory system on EFT; particularly, it increased the time required to construct a standard familiar episodic future event, but did not significantly affect novel episodic event reaction time. Collectively, these findings support the hypothesis that event familiarity importantly moderates episodic and semantic memory's contribution to EFT.

Type-specific proactive interference in patients with semantic and phonological STM deficits.

PubMed

Harris, Lara; Olson, Andrew; Humphreys, Glyn

2014-01-01

Prior neuropsychological evidence suggests that semantic and phonological components of short-term memory (STM) are functionally and neurologically distinct. The current paper examines proactive interference (PI) from semantic and phonological information in two STM-impaired patients, DS (semantic STM deficit) and AK (phonological STM deficit). In Experiment 1 probe recognition tasks with open and closed sets of stimuli were used. Phonological PI was assessed using nonword items, and semantic and phonological PI was assessed using words. In Experiment 2 phonological and semantic PI was elicited by an item recognition probe test with stimuli that bore phonological and semantic relations to the probes. The data suggested heightened phonological PI for the semantic STM patient, and exaggerated effects of semantic PI in the phonological STM case. The findings are consistent with an account of extremely rapid decay of activated type-specific representations in cases of severely impaired phonological and semantic STM.

The effects of gender on the retrieval of episodic and semantic components of autobiographical memory.

PubMed

Fuentes, Amanda; Desrocher, Mary

2013-01-01

Despite consistent evidence that women exhibit greater episodic memory specificity than men, little attention has been paid to gender differences in the production of episodic details during autobiographical recall under conditions of high and low retrieval support. Similarly the role of gender on the production of semantic details used to support autobiographical memory recollections of specific events has been largely unexplored. In the present study an undergraduate sample of 50 men and 50 women were assessed using the Autobiographical Interview (Levine, Svoboda, Hay, Winocur, & Moscovitch, 2002). Women recalled more episodic information compared to men in the high retrieval support condition, whereas no gender differences were found in the low retrieval support condition. In addition, women produced more repetitions compared to men in the high retrieval support condition. No gender differences were found in the production of semantic details. These results are interpreted in terms of gender differences in encoding and reminiscence practices. This research adds to the literature on gender differences in memory recall and suggests that gender is an important variable in explaining individual differences in AM recall.

Autobiographical memory in semantic dementia: implication for theories of limbic-neocortical interaction in remote memory.

PubMed

McKinnon, Margaret C; Black, Sandra E; Miller, Bruce; Moscovitch, Morris; Levine, Brian

2006-01-01

We examined autobiographical memory performance in two patients with semantic dementia using a novel measure, the Autobiographical Interview [Levine, Svoboda, Hay, Winocur, & Moscovitch (2002). Aging and autobiographical memory: Dissociating episodic from semantic retrieval. Psychology and Aging, 17, 677-689], that is capable of dissociating episodic and personal semantic recall under varying levels of retrieval support. Earlier reports indicated that patients with semantic dementia demonstrate autobiographical episodic memory loss following a "reverse gradient" by which recent memories are preserved relative to remote memories. We found limited evidence for this pattern at conditions of low retrieval support. When structured probing was provided, patients' autobiographical memory performance was similar to that of controls. Retesting of one patient after 1 year indicated that retrieval support was insufficient to bolster performance following progressive prefrontal volume loss, as documented with quantified structural neuroimaging. These findings are discussed in relation to theories of limbic-neocortical interaction in autobiographical memory.

Acute effects of exergames on cognitive function of institutionalized older persons: a single-blinded, randomized and controlled pilot study.

PubMed

Monteiro-Junior, Renato Sobral; da Silva Figueiredo, Luiz Felipe; Maciel-Pinheiro, Paulo de Tarso; Abud, Erick Lohan Rodrigues; Braga, Ana Elisa Mendes Montalvão; Barca, Maria Lage; Engedal, Knut; Nascimento, Osvaldo José M; Deslandes, Andrea Camaz; Laks, Jerson

2017-06-01

Improvements on balance, gait and cognition are some of the benefits of exergames. Few studies have investigated the cognitive effects of exergames in institutionalized older persons. To assess the acute effect of a single session of exergames on cognition of institutionalized older persons. Nineteen institutionalized older persons were randomly allocated to Wii (WG, n = 10, 86 ± 7 year, two males) or control groups (CG, n = 9, 86 ± 5 year, one male). The WG performed six exercises with virtual reality, whereas CG performed six exercises without virtual reality. Verbal fluency test (VFT), digit span forward and digit span backward were used to evaluate semantic memory/executive function, short-term memory and work memory, respectively, before and after exergames and Δ post- to pre-session (absolute) and Δ % (relative) were calculated. Parametric (t independent test) and nonparametric (Mann-Whitney test) statistics and effect size were applied to tests for efficacy. VFT was statistically significant within WG (-3.07, df = 9, p = 0.013). We found no statistically significant differences between the two groups (p > 0.05). Effect size between groups of Δ % (median = 21 %) showed moderate effect for WG (0.63). Our data show moderate improvement of semantic memory/executive function due to exergames session. It is possible that cognitive brain areas are activated during exergames, increasing clinical response. A single session of exergames showed no significant improvement in short-term memory, working memory and semantic memory/executive function. The effect size for verbal fluency was promising, and future studies on this issue should be developed. RBR-6rytw2.

Effects of Orthographic, Morphological and Semantic Overlap on Short-Term Memory for Words in Typical and Atypical Development

ERIC Educational Resources Information Center

Breadmore, Helen L.; Carroll, Julia M.

2016-01-01

Little is known about implicit morphological processing in typical and atypical readers. These studies investigate this using a probe detection task with lures sharing morphological, orthographic, or semantic overlap with the probe. Intermediate and advanced readers (reading ages = 9;1-12;9) perform more poorly when there is more linguistic…

Paced Reading in Semantic Dementia: Word Knowledge Contributes to Phoneme Binding in Rapid Speech Production

ERIC Educational Resources Information Center

Jefferies, Elizabeth; Grogan, John; Mapelli, Cristina; Isella, Valeria

2012-01-01

Patients with semantic dementia (SD) show deficits in phoneme binding in immediate serial recall: when attempting to reproduce a sequence of words that they no longer fully understand, they show frequent migrations of phonemes between items (e.g., cap, frog recalled as "frap, cog"). This suggests that verbal short-term memory emerges directly from…

The effects of bilingual language proficiency on recall accuracy and semantic clustering in free recall output: evidence for shared semantic associations across languages.

PubMed

Francis, Wendy S; Taylor, Randolph S; Gutiérrez, Marisela; Liaño, Mary K; Manzanera, Diana G; Penalver, Renee M

2018-05-19

Two experiments investigated how well bilinguals utilise long-standing semantic associations to encode and retrieve semantic clusters in verbal episodic memory. In Experiment 1, Spanish-English bilinguals (N = 128) studied and recalled word and picture sets. Word recall was equivalent in L1 and L2, picture recall was better in L1 than in L2, and the picture superiority effect was stronger in L1 than in L2. Semantic clustering in word and picture recall was equivalent in L1 and L2. In Experiment 2, Spanish-English bilinguals (N = 128) and English-speaking monolinguals (N = 128) studied and recalled word sequences that contained semantically related pairs. Data were analyzed using a multinomial processing tree approach, the pair-clustering model. Cluster formation was more likely for semantically organised than for randomly ordered word sequences. Probabilities of cluster formation, cluster retrieval, and retrieval of unclustered items did not differ across languages or language groups. Language proficiency has little if any impact on the utilisation of long-standing semantic associations, which are language-general.

Shared Semantics and the Use of Organizational Memories for E-Mail Communications.

ERIC Educational Resources Information Center

Schwartz, David G.

1998-01-01

Examines the use of shared semantics information to link concepts in an organizational memory to e-mail communications. Presents a framework for determining shared semantics based on organizational and personal user profiles. Illustrates how shared semantics are used by the HyperMail system to help link organizational memories (OM) content to…

Developmental amnesia: Fractionation of developing memory systems.

PubMed

Temple, Christine M; Richardson, Paul

2006-07-01

Study of the developmental amnesias utilizing a cognitive neuropsychological methodology has highlighted the dissociations that may occur between the development of components of memory. M.M., a new case of developmental amnesia, was identified after screening from the normal population on cognitive and memory measures. Retrospective investigation found that he was of low birthweight. M.M. had impaired semantic memory for knowledge of facts and words. There was impaired episodic memory for words and stories but intact episodic memory for visual designs and features. This forms a double dissociation with Dr S. (Temple, 1992), who had intact verbal but impaired visual episodic memory. M.M. also had impaired autobiographical episodic memory. Nevertheless, learning over repeated trials occurred, consistent with previous theorizing that learning is not simply the effect of recurrent episodic memory. Nor is it the same as establishing semantic memory, since for M.M. semantic memory is also impaired. Within reading, there was an impaired lexico-semantic system, elevated levels of homophone confusion, but intact phonological reading, consistent with surface dyslexia and raising issues about the interrelationship of the semantic system and literacy development. The results are compatible with discrete semi-independent components within memory development, whereby deficits are associated with residual normality, but there may also be an explicit relationship between the semantic memory system and both vocabulary and reading acquisition.

Working memory and executive functions in transient global amnesia.

PubMed

Quinette, Peggy; Guillery, Bérengère; Desgranges, Béatrice; de la Sayette, Vincent; Viader, Fausto; Eustache, Francis

2003-09-01

Transient global amnesia (TGA) is usually considered to produce a profound impairment of long-term episodic memory, while at the same time sparing working memory. However, this neuropsychological dissociation has rarely been examined in detail. While a few studies have assessed some components of working memory in TGA, the results that have been obtained are far from conclusive. To clarify this issue, we carried out a comprehensive investigation of working memory in 10 patients during a TGA attack. In the first study, we report the results from three patients examined with a battery of neuropsychological tests designed to assess each of the three subcomponents of Baddeley's model of working memory. In a second study, seven different patients underwent neuropsychological investigations that focused specifically on the central executive system, using a protocol derived from a study by Miyake and colleagues. Our findings showed that subcomponents of working memory, such as the phonological loop and visuo-spatial sketch pad, were spared in TGA patients. Specific executive functions that entailed inhibitory control, dual task performance, updating and shifting mechanisms were also found to be normal. However, we found significantly impaired performance for the Brown-Peterson test, and that TGA patients were significantly impaired in the recollection of their episodic memories. They also made reduced numbers of 'remember' compared with 'know' judgments in the episodic memory test several days after TGA. On the basis of our findings, it would appear that the episodic memory deficit during TGA is not related to elementary aspects of executive functioning. Our data also highlight the nature of the cognitive mechanisms involved in the Brown-Peterson task, which may well depend on long-term memory (such as the process of semantic encoding). Lastly, the selective deficit in recollective episodic memories observed in TGA may be principally related to medial temporal lobe abnormalities that have been reported in this syndrome.

Autobiographical Memory in Semantic Dementia: A Longitudinal fMRI Study

ERIC Educational Resources Information Center

Maguire, Eleanor A.; Kumaran, Dharshan; Hassabis, Demis; Kopelman, Michael D.

2010-01-01

Whilst patients with semantic dementia (SD) are known to suffer from semantic memory and language impairments, there is less agreement about whether memory for personal everyday experiences, autobiographical memory, is compromised. In healthy individuals, functional MRI (fMRI) has helped to delineate a consistent and distributed brain network…

The Influence of Age-Related Differences in Prior Knowledge and Attentional Refreshing Opportunities on Episodic Memory.

PubMed

Loaiza, Vanessa M; Rhodes, Matthew G; Anglin, Julia

2015-09-01

The assumption that working memory (WM) is embedded within long-term memory suggests that the effectiveness of switching information between activated states in WM (i.e., attentional refreshing) may depend on whether that information is semantically relevant. Given that older adults often have greater general knowledge than younger adults, age-related deficits in episodic memory (EM) could be ameliorated by studying information that has existing semantic representations compared with unknown information. Younger and older adults completed a modified operation span task that varied the number of refreshing opportunities. The memoranda used were equally known to younger and older adults (neutral words; e.g., father), better known to older adults than younger adults (dated words; e.g., mirth), or unknown to both groups (unknown words; e.g., cobot). Results for immediate and delayed recall indicated an age-related improvement for dated memoranda and no age difference for unknown memoranda. Furthermore, refreshing opportunities predicted delayed recall of neutral memoranda more strongly for younger adults than older adults, whereas older adults' recall advantage for dated memoranda was explained by their prior knowledge and not refreshing opportunities. The results suggest that older adults' EM deficits could potentially be ameliorated by incorporating their superior knowledge to supplement relatively ineffective attentional refreshing in WM. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Remote semantic memory for public figures in HIV infection, alcoholism, and their comorbidity.

PubMed

Fama, Rosemary; Rosenbloom, Margaret J; Sassoon, Stephanie A; Thompson, Megan A; Pfefferbaum, Adolf; Sullivan, Edith V

2011-02-01

Impairments in component processes of working and episodic memory mark both HIV infection and chronic alcoholism, with compounded deficits often observed in individuals comorbid for these conditions. Remote semantic memory processes, however, have only seldom been studied in these diagnostic groups. Examination of remote semantic memory could provide insight into the underlying processes associated with storage and retrieval of learned information over extended time periods while elucidating spared and impaired cognitive functions in these clinical groups. We examined component processes of remote semantic memory in HIV infection and chronic alcoholism in 4 subject groups (HIV, ALC, HIV + ALC, and age-matched healthy adults) using a modified version of the Presidents Test. Free recall, recognition, and sequencing of presidential candidates and election dates were assessed. In addition, component processes of working, episodic, and semantic memory were assessed with ancillary cognitive tests. The comorbid group (HIV + ALC) was significantly impaired on sequencing of remote semantic information compared with age-matched healthy adults. Free recall of remote semantic information was also modestly impaired in the HIV + ALC group, but normal performance for recognition of this information was observed. Few differences were observed between the single diagnosis groups (HIV, ALC) and healthy adults, although examination of the component processes underlying remote semantic memory scores elicited differences between the HIV and ALC groups. Selective remote memory processes were related to lifetime alcohol consumption in the ALC group and to viral load and depression level in the HIV group. Hepatitis C diagnosis was associated with lower remote semantic memory scores in all 3 clinical groups. Education level did not account for group differences reported. This study provides behavioral support for the existence of adverse effects associated with the comorbidity of HIV infection and chronic alcoholism on selective component processes of memory function, with untoward effects exacerbated by Hepatitis C infection. The pattern of remote semantic memory function in HIV + ALC is consistent with those observed in neurological conditions primarily affecting frontostriatal pathways and suggests that remote memory dysfunction in HIV + ALC may be a result of impaired retrieval processes rather than loss of remote semantic information per se. Copyright © 2010 by the Research Society on Alcoholism.

Cue-dependent interference in comprehension

PubMed Central

Van Dyke, Julie A.

2011-01-01

The role of interference as a primary determinant of forgetting in memory has long been accepted, however its role as a contributor to poor comprehension is just beginning to be understood. The current paper reports two studies, in which speed-accuracy tradeoff and eye-tracking methodologies were used with the same materials to provide converging evidence for the role of syntactic and semantic cues as mediators of both proactive (PI) and retroactive interference (RI) during comprehension. Consistent with previous work (e.g., Van Dyke & Lewis, 2003), we found that syntactic constraints at the retrieval site are among the cues that drive retrieval in comprehension, and that these constraints effectively limit interference from potential distractors with semantic/pragmatic properties in common with the target constituent. The data are discussed in terms of a cue-overload account, in which interference both arises from and is mediated through a direct-access retrieval mechanism that utilizes a linear, weighted cue-combinatoric scheme. PMID:21927535

Science and Technology Text Mining: Text Mining of the Journal Cortex

DTIC Science & Technology

2004-01-01

Amnesia Retrograde Amnesia GENERAL Semantic Memory Episodic Memory Working Memory TEST Serial Position Curve...in Cortex can be reasonably divided into four categories (papers in each category in parenthesis): Semantic Memory (151); Handedness (145); Amnesia ... Semantic Memory (151) is divided into Verbal/ Numerical (76) and Visual/ Spatial (75). Amnesia (119) is divided into Amnesia Symptoms (50) and

Longitudinal Study of a Novel Performance-based Measure of Daily Function

DTIC Science & Technology

2015-04-01

measures of cognition (e.g., episodic memory , semantic memory , executive function, speed). We found that patients with MCI had compromises in...UPSA, as well as measures of cognition (e.g., episodic memory , semantic memory , executive function, speed). We found that patients with MCI had... memory , semantic memory , executive function, speed). We found that patients with MCI had compromises in everyday functional competence and that the

Effects of Interactive Vocabulary Instruction on the Vocabulary Learning and Reading Comprehension of Junior-High Learning Disabled Students.

ERIC Educational Resources Information Center

Bos, Candace S.; Anders, Patricia L.

1990-01-01

The study, involving 61 learning-disabled junior high students, compared the short-term and long-term effectiveness of definition instruction with interactive vocabulary strategies (semantic mapping, semantic feature analysis, and semantic/syntactic feature analysis). Students participating in the interactive strategies demonstrated greater…

Brain lateralization and neural plasticity for musical and cognitive abilities in an epileptic musician

PubMed Central

Trujillo-Pozo, Isabel; Martín-Monzón, Isabel; Rodríguez-Romero, Rafael

2013-01-01

The use of intracarotid propofol procedure (IPP) when assessing musical lateralization has not been reported in literature up to now. This procedure (similar to Wada Test) has provided the opportunity to investigate not only lateralization of language and memory functions on epileptic patients but also offers a functional mapping approach with superior spatial and temporal resolution to analyze the lateralization of musical abilities. Findings in literature suggest that musical training modifies functional and structural brain organization. We studied hemispheric lateralization in a professional musician, a 33 years old woman with refractory left medial temporal lobe (MTL) epilepsy (TLE). A longitudinal neuropsychological study was performed over a period of 21 months. Before epilepsy surgery, musical abilities, language and memory were tested during IPP by means of a novel and exhaustive neuropsychological battery focusing on the processing of music. We used a selection of stimuli to analyze listening, score reading, and tempo discrimination. Our results suggested that IPP is an excellent method to determine not only language, semantic, and episodic memory, but also musical dominance in a professional musician who may be candidate for epilepsy surgery. Neuropsychological testing revealed that right hemisphere's patient is involved in semantic and episodic musical memory processes, whereas her score reading and tempo processing require contribution from both hemispheres. At one-year follow-up, outcome was excellent with respect to seizures and professional skills, meanwhile cognitive abilities improved. These findings indicate that IPP helps to predict who might be at risk for postoperative musical, language, and memory deficits after epilepsy surgery. Our research suggests that musical expertise and epilepsy critically modifies long-term memory processes and induces brain structural and functional plasticity. PMID:24367312

Beyond the Memory Mechanism: Person-Selective and Nonselective Processes in Recognition of Personally Familiar Faces

ERIC Educational Resources Information Center

Sugiura, Motoaki; Mano, Yoko; Sasaki, Akihiro; Sadato, Norihiro

2011-01-01

Special processes recruited during the recognition of personally familiar people have been assumed to reflect the rich episodic and semantic information that selectively represents each person. However, the processes may also include person nonselective ones, which may require interpretation in terms beyond the memory mechanism. To examine this…

Using semantic memory to boost 'episodic' recall in a case of developmental amnesia.

PubMed

Brandt, Karen R; Gardiner, John M; Vargha-Khadem, Faraneh; Baddeley, Alan D; Mishkin, Mortimer

2006-07-17

We report two experiments that investigated factors that might boost 'episodic' recall for Jon, a developmental amnesic whose episodic memory is gravely impaired but whose semantic memory seems relatively normal. Experiment 1 showed that Jon's recall improved following a semantic study task compared with a non-semantic study task, as well as following four repeated study trials compared with only one. Experiment 2 additionally revealed that Jon's recall improved after acting compared with reading action phrases at study, but only if the phrases were well integrated semantically. The results provide some support for the hypothesis that Jon's 'episodic' recall depends on the extent to which he is able to retrieve events using semantic memory.

Autobiographically significant concepts: more episodic than semantic in nature? An electrophysiological investigation of overlapping types of memory.

PubMed

Renoult, Louis; Davidson, Patrick S R; Schmitz, Erika; Park, Lillian; Campbell, Kenneth; Moscovitch, Morris; Levine, Brian

2015-01-01

A common assertion is that semantic memory emerges from episodic memory, shedding the distinctive contexts associated with episodes over time and/or repeated instances. Some semantic concepts, however, may retain their episodic origins or acquire episodic information during life experiences. The current study examined this hypothesis by investigating the ERP correlates of autobiographically significant (AS) concepts, that is, semantic concepts that are associated with vivid episodic memories. We inferred the contribution of semantic and episodic memory to AS concepts using the amplitudes of the N400 and late positive component, respectively. We compared famous names that easily brought to mind episodic memories (high AS names) against equally famous names that did not bring such recollections to mind (low AS names) on a semantic task (fame judgment) and an episodic task (recognition memory). Compared with low AS names, high AS names were associated with increased amplitude of the late positive component in both tasks. Moreover, in the recognition task, this effect of AS was highly correlated with recognition confidence. In contrast, the N400 component did not differentiate the high versus low AS names but, instead, was related to the amount of general knowledge participants had regarding each name. These results suggest that semantic concepts high in AS, such as famous names, have an episodic component and are associated with similar brain processes to those that are engaged by episodic memory. Studying AS concepts may provide unique insights into how episodic and semantic memory interact.

Episodic Memory, Semantic Memory, and Fluency.

ERIC Educational Resources Information Center

Schaefer, Carl F.

1980-01-01

Suggests that creating a second-language semantic network can be conceived as developing a plan for retrieving second-language word forms. Characteristics of linguistic performance which will promote fluency are discussed in light of the distinction between episodic and semantic memory. (AMH)

Sentence Verification, Sentence Recognition, and the Semantic-Episodic Distinction

ERIC Educational Resources Information Center

Shoben, Edward J.; And Others

1978-01-01

In an attempt to assess the validity of the distinction between episodic and semantic memory, this research examined the influence of two variables on sentence verification (presumably a semantic memory task) and sentence recognition (presumably an episodic memory task). ( Editor)

Eye Movements and Visual Memory for Scenes

DTIC Science & Technology

2005-01-01

Scene memory research has demonstrated that the memory representation of a semantically inconsistent object in a scene is more detailed and/or complete... memory during scene viewing, then changes to semantically inconsistent objects (which should be represented more com- pletely) should be detected more... semantic description. Due to the surprise nature of the visual memory test, any learning that occurred during the search portion of the experiment was

Working memory training and semantic structuring improves remembering future events, not past events.

PubMed

Richter, Kim Merle; Mödden, Claudia; Eling, Paul; Hildebrandt, Helmut

2015-01-01

Objectives. Memory training in combination with practice in semantic structuring and word fluency has been shown to improve memory performance. This study investigated the efficacy of a working memory training combined with exercises in semantic structuring and word fluency and examined whether training effects generalize to other cognitive tasks. Methods. In this double-blind randomized control study, 36 patients with memory impairments following brain damage were allocated to either the experimental or the active control condition, with both groups receiving 9 hours of therapy. The experimental group received a computer-based working memory training and exercises in word fluency and semantic structuring. The control group received the standard memory therapy provided in the rehabilitation center. Patients were tested on a neuropsychological test battery before and after therapy, resulting in composite scores for working memory; immediate, delayed, and prospective memory; word fluency; and attention. Results. The experimental group improved significantly in working memory and word fluency. The training effects also generalized to prospective memory tasks. No specific effect on episodic memory could be demonstrated. Conclusion. Combined treatment of working memory training with exercises in semantic structuring is an effective method for cognitive rehabilitation of organic memory impairment. © The Author(s) 2014.

Right ventral frontal hypometabolism and abnormal sense of self in a case of disproportionate retrograde amnesia.

PubMed

Piolino, Pascale; Hannequin, Didier; Desgranges, Beatrice; Girard, Carole; Beaunieux, Helene; Giffard, Benedicte; Lebreton, Karine; Eustache, Francis

2005-01-01

We report the case of a 42-year-old man (patient CL) who developed a particular profile of amnesia with two dates of onset. At the first onset, the patient suffered a mild/lmoderate injury that accounts for an initial anterograde and mild retrograde memory impairment. At the second onset, 8 months later, he suffered a sudden and persistent loss of personal identity and severe retrograde amnesia. We report an extensive neuropsychological investigation of his memory systems carried out 18 months after the second onset. Results indicated mild executive dysfunction (primary memory), intact procedural skills and perceptual representational system. In accordance with Kopelman's methodological recommendations, we have reliably compared post- and pre-onset semantic and episodic memory using strict matched procedures. We found that post-onset, though not pre-onset semantic (autobiographical and nonautobiographical) memory was entirely preserved. Post-onset episodic autobiographical memory was not intact, however, although it was clearly less affected compared with the total absence of the pre-onset memory. Moreover, a novel and high standard investigation of the subjective states of consciousness, which accompanied retrieval of autobiographical memories via the Remember/lKnow (R/lK) paradigm with a long time interval from the present, demonstrated a deterioration of R responses compared to matched controls. Interestingly, this result showed deficient autonoetic consciousness and suggested an underlying accelerated forgetting rate for post-onset autobiographical episodic memories. Last, a [18F] fluorodeoxyglucose resting PET study revealed a significant right-sided ventral frontal lobe hypometabolism in the absence of overt structural lesions. The involvement of this region is consistent with CL's autobiographical retrograde amnesia and his inability to re-experience information concerning the self across time. In our particular case, characterised by two dates of onset, the attribution of causality is thoroughly examined in terms of CL's organic and psychogenic aspects.

The Cognitive and Neural Expression of Semantic Memory Impairment in Mild Cognitive Impairment and Early Alzheimer's Disease

ERIC Educational Resources Information Center

Joubert, Sven; Brambati, Simona M.; Ansado, Jennyfer; Barbeau, Emmanuel J.; Felician, Olivier; Didic, Mira; Lacombe, Jacinthe; Goldstein, Rachel; Chayer, Celine; Kergoat, Marie-Jeanne

2010-01-01

Semantic deficits in Alzheimer's disease have been widely documented, but little is known about the integrity of semantic memory in the prodromal stage of the illness. The aims of the present study were to: (i) investigate naming abilities and semantic memory in amnestic mild cognitive impairment (aMCI), early Alzheimer's disease (AD) compared to…

Integrating across Episodes: Investigating the Long-term Accessibility of Self-derived Knowledge in 4-Year-Old Children

PubMed Central

Varga, Nicole L.; Stewart, Rebekah A.; Bauer, Patricia J.

2016-01-01

Semantic memory, defined as our store of knowledge about the world, provides representational support for all of our higher order cognitive functions. As such, it is crucial that the contents of semantic memory remain accessible over time. Although memory for knowledge learned through direct observation has been previously investigated, we know very little about the retention of knowledge derived through integration of information acquired across separate learning episodes. The present research investigated cross-episode integration in 4-year-old children. Participants were presented with novel facts via distinct story episodes and tested for knowledge extension through cross-episode integration, as well as for retention of the information over a 1-week delay. In Experiment 1, children retained the self-derived knowledge over the delay, though performance was primarily evidenced in a forced-choice format. In Experiment 2, we sought to facilitate the accessibility and robustness of self-derived knowledge by providing a verbal reminder after the delay. The accessibility of self-derived knowledge increased, irrespective of whether participants successfully demonstrated knowledge of the integration facts during the first visit. The results suggest knowledge extended through integration remains accessible after delays, even in a population in which this learning process is less robust. The findings also demonstrate the facilitative effect of reminders on the accessibility and further extension of knowledge over extended time periods. PMID:26774259

Supporting the self-concept with memory: insight from amnesia

PubMed Central

Verfaellie, Mieke

2015-01-01

We investigated the extent to which personal semantic memory supports the self-concept in individuals with medial temporal lobe amnesia and healthy adults. Participants completed eight ‘I Am’ self-statements. For each of the four highest ranked self-statements, participants completed an open-ended narrative task, during which they provided supporting information indicating why the I Am statement was considered self-descriptive. Participants then completed an episodic probe task, during which they attempted to retrieve six episodic memories for each of these self-statements. Supporting information was scored as episodic, personal semantic or general semantic. In the narrative task, personal semantic memory predominated as self-supporting information in both groups. The amnesic participants generated fewer personal semantic memories than controls to support their self-statements, a deficit that was more pronounced for trait relative to role self-statements. In the episodic probe task, the controls primarily generated unique event memories, but the amnesic participants did not. These findings demonstrate that personal semantic memory, in particular autobiographical fact knowledge, plays a critical role in supporting the self-concept, regardless of the accessibility of episodic memories, and they highlight potential differences in the way traits and roles are supported by personal memory. PMID:25964501

Visual working memory buffers information retrieved from visual long-term memory.

PubMed

Fukuda, Keisuke; Woodman, Geoffrey F

2017-05-16

Human memory is thought to consist of long-term storage and short-term storage mechanisms, the latter known as working memory. Although it has long been assumed that information retrieved from long-term memory is represented in working memory, we lack neural evidence for this and need neural measures that allow us to watch this retrieval into working memory unfold with high temporal resolution. Here, we show that human electrophysiology can be used to track information as it is brought back into working memory during retrieval from long-term memory. Specifically, we found that the retrieval of information from long-term memory was limited to just a few simple objects' worth of information at once, and elicited a pattern of neurophysiological activity similar to that observed when people encode new information into working memory. Our findings suggest that working memory is where information is buffered when being retrieved from long-term memory and reconcile current theories of memory retrieval with classic notions about the memory mechanisms involved.

Visual working memory buffers information retrieved from visual long-term memory

PubMed Central

Fukuda, Keisuke; Woodman, Geoffrey F.

2017-01-01

Human memory is thought to consist of long-term storage and short-term storage mechanisms, the latter known as working memory. Although it has long been assumed that information retrieved from long-term memory is represented in working memory, we lack neural evidence for this and need neural measures that allow us to watch this retrieval into working memory unfold with high temporal resolution. Here, we show that human electrophysiology can be used to track information as it is brought back into working memory during retrieval from long-term memory. Specifically, we found that the retrieval of information from long-term memory was limited to just a few simple objects’ worth of information at once, and elicited a pattern of neurophysiological activity similar to that observed when people encode new information into working memory. Our findings suggest that working memory is where information is buffered when being retrieved from long-term memory and reconcile current theories of memory retrieval with classic notions about the memory mechanisms involved. PMID:28461479

Episodic and Semantic Autobiographical Memory in Adults with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Crane, Laura; Goddard, Lorna

2008-01-01

Episodic and semantic autobiographical memories were examined in a group of adults with autism spectrum disorders (ASD) and a control group matched for age, gender and IQ. Results demonstrated a personal episodic memory deficit in the ASD group in the absence of a personal semantic memory deficit, suggesting a deficit dissociation between these…

Long-term memory and volatility clustering in high-frequency price changes

NASA Astrophysics Data System (ADS)

oh, Gabjin; Kim, Seunghwan; Eom, Cheoljun

2008-02-01

We studied the long-term memory in diverse stock market indices and foreign exchange rates using Detrended Fluctuation Analysis (DFA). For all high-frequency market data studied, no significant long-term memory property was detected in the return series, while a strong long-term memory property was found in the volatility time series. The possible causes of the long-term memory property were investigated using the return data filtered by the AR(1) model, reflecting the short-term memory property, the GARCH(1,1) model, reflecting the volatility clustering property, and the FIGARCH model, reflecting the long-term memory property of the volatility time series. The memory effect in the AR(1) filtered return and volatility time series remained unchanged, while the long-term memory property diminished significantly in the volatility series of the GARCH(1,1) filtered data. Notably, there is no long-term memory property, when we eliminate the long-term memory property of volatility by the FIGARCH model. For all data used, although the Hurst exponents of the volatility time series changed considerably over time, those of the time series with the volatility clustering effect removed diminish significantly. Our results imply that the long-term memory property of the volatility time series can be attributed to the volatility clustering observed in the financial time series.

Effects of Presentation Format and List Length on Children's False Memories

ERIC Educational Resources Information Center

Swannell, Ellen R.; Dewhurst, Stephen A.

2013-01-01

The effect of list length on children's false memories was investigated using list and story versions of the Deese/Roediger-McDermott procedure. Short (7 items) and long (14 items) sequences of semantic associates were presented to children aged 6, 8, and 10 years old either in lists or embedded within a story that emphasized the list theme.…

The Effect of Consistency on Short-Term Memory for Scenes.

PubMed

Gong, Mingliang; Xuan, Yuming; Xu, Xinwen; Fu, Xiaolan

2017-01-01

Which is more detectable, the change of a consistent or an inconsistent object in a scene? This question has been debated for decades. We noted that the change of objects in scenes might simultaneously be accompanied with gist changes. In the present study we aimed to examine how the alteration of gist, as well as the consistency of the changed objects, modulated change detection. In Experiment 1, we manipulated the semantic content by either keeping or changing the consistency of the scene. Results showed that the changes of consistent and inconsistent scenes were equally detected. More importantly, the changes were more accurately detected when scene consistency changed than when the consistency remained unchanged, regardless of the consistency of the memory scenes. A phase-scrambled version of stimuli was adopted in Experiment 2 to decouple the possible confounding effect of low-level factors. The results of Experiment 2 demonstrated that the effect found in Experiment 1 was indeed due to the change of high-level semantic consistency rather than the change of low-level physical features. Together, the study suggests that the change of consistency plays an important role in scene short-term memory, which might be attributed to the sensitivity to the change of semantic content.

The Effect of Consistency on Short-Term Memory for Scenes

PubMed Central

Gong, Mingliang; Xuan, Yuming; Xu, Xinwen; Fu, Xiaolan

2017-01-01

Which is more detectable, the change of a consistent or an inconsistent object in a scene? This question has been debated for decades. We noted that the change of objects in scenes might simultaneously be accompanied with gist changes. In the present study we aimed to examine how the alteration of gist, as well as the consistency of the changed objects, modulated change detection. In Experiment 1, we manipulated the semantic content by either keeping or changing the consistency of the scene. Results showed that the changes of consistent and inconsistent scenes were equally detected. More importantly, the changes were more accurately detected when scene consistency changed than when the consistency remained unchanged, regardless of the consistency of the memory scenes. A phase-scrambled version of stimuli was adopted in Experiment 2 to decouple the possible confounding effect of low-level factors. The results of Experiment 2 demonstrated that the effect found in Experiment 1 was indeed due to the change of high-level semantic consistency rather than the change of low-level physical features. Together, the study suggests that the change of consistency plays an important role in scene short-term memory, which might be attributed to the sensitivity to the change of semantic content. PMID:29046654

False memory for orthographically versus semantically similar words in adolescents with dyslexia: a fuzzy-trace theory perspective.

PubMed

Obidziński, Michał; Nieznański, Marek

2017-10-01

The presented research was conducted in order to investigate the connections between developmental dyslexia and the functioning of verbatim and gist memory traces-assumed in the fuzzy-trace theory. The participants were 71 high school students (33 with dyslexia and 38 without learning difficulties). The modified procedure and multinomial model of Stahl and Klauer (simplified conjoint recognition model) was used to collect and analyze data. Results showed statistically significant differences in four of the model parameters: (a) the probability of verbatim trace recollection upon presentation of orthographically similar stimulus was higher in the control than dyslexia group, (b) the probability of verbatim trace recollection upon presentation of semantically similar stimulus was higher in the control than dyslexia group, (c) the probability of gist trace retrieval upon presentation of semantically similar stimulus was higher in the dyslexia than control group, and (d) the probability of gist trace retrieval upon target stimulus presentation (in the semantic condition) was higher in the control than dyslexia group. The obtained results suggest differences of memory functioning in terms of verbatim and gist trace retrieval between people with and without dyslexia on specific, elementary cognitive processes postulated by the fuzzy-trace theory. These can indicate new approaches in the education of persons with developmental dyslexia, focused on specific impairments and the strengths of their memory functioning.

The inferior, anterior temporal lobes and semantic memory clarified: novel evidence from distortion-corrected fMRI.

PubMed

Visser, M; Embleton, K V; Jefferies, E; Parker, G J; Ralph, M A Lambon

2010-05-01

The neural basis of semantic memory generates considerable debate. Semantic dementia results from bilateral anterior temporal lobe (ATL) atrophy and gives rise to a highly specific impairment of semantic memory, suggesting that this region is a critical neural substrate for semantic processing. Recent rTMS experiments with neurologically-intact participants also indicate that the ATL are a necessary substrate for semantic memory. Exactly which regions within the ATL are important for semantic memory are difficult to detect from these methods (because the damage in SD covers a large part of the ATL). Functional neuroimaging might provide important clues about which specific areas exhibit activation that correlates with normal semantic performance. Neuroimaging studies, however, have not consistently found anterior temporal lobe activation in semantic tasks. A recent meta-analysis indicates that this inconsistency may be due to a collection of technical limitations associated with previous studies, including a reduced field-of-view and magnetic susceptibility artefacts associated with standard gradient echo fMRI. We conducted an fMRI study of semantic memory using a combination of techniques which improve sensitivity to ATL activations whilst preserving whole-brain coverage. As expected from SD patients and ATL rTMS experiments, this method revealed bilateral temporal activation extending from the inferior temporal lobe along the fusiform gyrus to the anterior temporal regions, bilaterally. We suggest that the inferior, anterior temporal lobe region makes a crucial contribution to semantic cognition and utilising this version of fMRI will enable further research on the semantic role of the ATL. 2010 Elsevier Ltd. All rights reserved.

Neural dynamics associated with semantic and episodic memory for faces: evidence from multiple frequency bands.

PubMed

Zion-Golumbic, Elana; Kutas, Marta; Bentin, Shlomo

2010-02-01

Prior semantic knowledge facilitates episodic recognition memory for faces. To examine the neural manifestation of the interplay between semantic and episodic memory, we investigated neuroelectric dynamics during the creation (study) and the retrieval (test) of episodic memories for famous and nonfamous faces. Episodic memory effects were evident in several EEG frequency bands: theta (4-8 Hz), alpha (9-13 Hz), and gamma (40-100 Hz). Activity in these bands was differentially modulated by preexisting semantic knowledge and by episodic memory, implicating their different functional roles in memory. More specifically, theta activity and alpha suppression were larger for old compared to new faces at test regardless of fame, but were both larger for famous faces during study. This pattern of selective semantic effects suggests that the theta and alpha responses, which are primarily associated with episodic memory, reflect utilization of semantic information only when it is beneficial for task performance. In contrast, gamma activity decreased between the first (study) and second (test) presentation of a face, but overall was larger for famous than nonfamous faces. Hence, the gamma rhythm seems to be primarily related to activation of preexisting neural representations that may contribute to the formation of new episodic traces. Taken together, these data provide new insights into the complex interaction between semantic and episodic memory for faces and the neural dynamics associated with mnemonic processes.

The Category Cued Recall test in very mild Alzheimer's disease: discriminative validity and correlation with semantic memory functions.

PubMed

Vogel, A; Mortensen, E L; Gade, A; Waldemar, G

2007-01-01

Episodic memory tests that measure cued recall may be particularly effective in the diagnosis of early Alzheimer's disease (AD) because they examine both episodic and semantic memory functions. The Category Cued Recall (CCR) test provides superordinate semantic cues at encoding and retrieval, and high discriminative validity has been claimed for this test. The aim of this study was to investigate the discriminative validity for this test when compared with the 10-word memory list from Alzheimer's Disease Assessment Scale (ADAS-cog) that measures free recall. The clinical diagnosis of AD was taken as the standard. It was also investigated whether the two episodic memory tests correlated with measures of semantic memory. The tests were administered to 35 patients with very mild AD (Mini Mental State Examination score >22) and 28 control subjects. Both tests had high sensitivity (>88%) with high specificity (>89%). One out of the five semantic memory tests was significantly correlated to performances on CCR, whereas delayed recall on the ADAS-cog memory test was significantly correlated to two semantic tests. In conclusion, the discriminative validity of the CCR test and the ADAS-cog memory test was equivalent in very mild AD. This may be because CCR did not tap more semantic processes, which are impaired in the earliest phases of AD, than a test of free recall.

The influence of autonomic arousal and semantic relatedness on memory for emotional words.

PubMed

Buchanan, Tony W; Etzel, Joset A; Adolphs, Ralph; Tranel, Daniel

2006-07-01

Increased memory for emotional stimuli is a well-documented phenomenon. Emotional arousal during the encoding of a stimulus is one mediator of this memory enhancement. Other variables such as semantic relatedness also play a role in the enhanced memory for emotional stimuli, especially for verbal stimuli. Research has not addressed the contributions of emotional arousal, indexed by self-report and autonomic measures, and semantic relatedness on memory performance. Twenty young adults (10 women) were presented neutral-unrelated words, school-related words, moderately arousing emotional words, and highly arousing taboo words while heart rate and skin conductance were measured. Memory was tested with free recall and recognition tests. Results showed that taboo words, which were both semantically related and high arousal were remembered best. School-related words, which were high on semantic relatedness but low on arousal, were remembered better than the moderately arousing emotional words and semantically unrelated neutral words. Psychophysiological responses showed that within the moderately arousing emotional and neutral word groups, those words eliciting greater autonomic activity were better remembered than words that did not elicit such activity. These results demonstrate additive effects of semantic relatedness and emotional arousal on memory. Relatedness confers an advantage to memory (as in the school-words), but the combination of relatedness and arousal (as in the taboo words) results in the best memory performance.

Lateral and medial prefrontal contributions to emotion generation by semantic elaboration during episodic encoding.

PubMed

Kaneda, Takumi; Shigemune, Yayoi; Tsukiura, Takashi

2017-02-01

Memories for emotion-laden stimuli are remembered more accurately than those for neutral stimuli. Although this enhancement reflects stimulus-driven modulation of memory by emotions, functional neuroimaging evidence of the interacting mechanisms between emotions generated by intentional processes, such as semantic elaboration, and memory is scarce. The present fMRI study investigated how encoding-related activation is modulated by emotions generated during the process of semantic elaboration. During encoding with fMRI, healthy young adults viewed neutral (target) pictures either passively or with semantic elaboration. In semantic elaboration, participants imagined background stories related to the pictures. Encoding trials with semantic elaboration were subdivided into conditions in which participants imagined negative, positive, or neutral stories. One week later, memories for target pictures were tested. In behavioral results, memories for target pictures were significantly enhanced by semantic elaboration, compared to passive viewing, and the memory enhancement was more remarkable when negative or positive stories were imagined. fMRI results demonstrated that activations in the left inferior frontal gyrus and dorsal medial prefrontal cortex (dmPFC) were greater during the encoding of target pictures with semantic elaboration than those with passive viewing, and that these activations further increased during encoding with semantic elaboration of emotional stories than of neutral stories. Functional connectivity between the left inferior frontal gyrus and dmPFC/hippocampus during encoding significantly predicted retrieval accuracies of memories encoded with self-generated emotional stories. These findings suggest that networks including the left inferior frontal region, dmPFC, and hippocampus could contribute to the modulation of memories encoded with the emotion generation.

[Evaluation of temporality semantic knowledge in normal aging and in mild and moderate stages of Alzheimer's disease].

PubMed

Rivasseau Jonveaux, T; Batt, M; Empereur, F; Braun, M; Trognon, A

2015-04-01

Episodic and semantic processes are involved in temporality used in daily life. Episodic memory permits one to place an event on the time axis, while semantic memory makes us aware of the time segmentation and its symbolic representation. Memory of the knowledge connected to the passing of time is materialized on the calendar and can be seen symbolically on the dial of a clock. In AD, semantic memory processes are preserved longer than processes related to episodic memory. We wonder whether the specific field of knowledge about time is altered during AD. We validated a specific evaluation with a control group (354 healthy subjects). Then we applied this battery to assess AD patients to appreciate the feasibility of this tool for this population. We then compared 22 AD patients with a control group matched for age, sex and educational level. Our clinical scale of temporal semantic knowledge consists of four parts: (a) hour reading with a.m. and p.m. hours; (b) using a clock: 12 clock faces with the hour numbers already placed: the patient draws hour and minute hands for various hours; (c) temporal segmentation: exploration of the knowledge on daytime scale and of the calendar; (d) time duration estimation: calculate how long the interview has lasted after indicating the time of its beginning and its end, then the time between 10.40 to 12.00. While age and educational level had an influence on all the scores, in the two groups control and patients, gender did not. Temporal segmentation, independent of the cultural level, revealed the best acquired knowledge in our control population. All the scores differentiated patients from control subjects. The temporal semantic knowledge correlated with the AD severity seemed to be correlated with the attention, verbal comprehension, and some components of executive functions, but was not related to the clock drawing test result. Depression did not have any influence on this scale in our AD group. The temporal semantic knowledge clinical scale shows differential alterations, notably in hour reading and using a clock, and less in temporal segmentation. Temporal semantic knowledge is altered in AD. The diagnosis and follow-up of these alterations allow professionals and caregivers to consider adaptations of the patient's environment according to their needs. Copyright © 2013 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Short-Term Memory and Aphasia: From Theory to Treatment.

PubMed

Minkina, Irene; Rosenberg, Samantha; Kalinyak-Fliszar, Michelene; Martin, Nadine

2017-02-01

This article reviews existing research on the interactions between verbal short-term memory and language processing impairments in aphasia. Theoretical models of short-term memory are reviewed, starting with a model assuming a separation between short-term memory and language, and progressing to models that view verbal short-term memory as a cognitive requirement of language processing. The review highlights a verbal short-term memory model derived from an interactive activation model of word retrieval. This model holds that verbal short-term memory encompasses the temporary activation of linguistic knowledge (e.g., semantic, lexical, and phonological features) during language production and comprehension tasks. Empirical evidence supporting this model, which views short-term memory in the context of the processes it subserves, is outlined. Studies that use a classic measure of verbal short-term memory (i.e., number of words/digits correctly recalled in immediate serial recall) as well as those that use more intricate measures (e.g., serial position effects in immediate serial recall) are discussed. Treatment research that uses verbal short-term memory tasks in an attempt to improve language processing is then summarized, with a particular focus on word retrieval. A discussion of the limitations of current research and possible future directions concludes the review. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Short-Term Memory and Aphasia: From Theory to Treatment

PubMed Central

Minkina, Irene; Rosenberg, Samantha; Kalinyak-Fliszar, Michelene; Martin, Nadine

2018-01-01

This article reviews existing research on the interactions between verbal short-term memory and language processing impairments in aphasia. Theoretical models of short-term memory are reviewed, starting with a model assuming a separation between short-term memory and language, and progressing to models that view verbal short-term memory as a cognitive requirement of language processing. The review highlights a verbal short-term memory model derived from an interactive activation model of word retrieval. This model holds that verbal short-term memory encompasses the temporary activation of linguistic knowledge (e.g., semantic, lexical, and phonological features) during language production and comprehension tasks. Empirical evidence supporting this model, which views short-term memory in the context of the processes it subserves, is outlined. Studies that use a classic measure of verbal short-term memory (i.e., number of words/digits correctly recalled in immediate serial recall) as well as those that use more intricate measures (e.g., serial position effects in immediate serial recall) are discussed. Treatment research that uses verbal short-term memory tasks in an attempt to improve language processing is then summarized, with a particular focus on word retrieval. A discussion of the limitations of current research and possible future directions concludes the review. PMID:28201834

Alpha Oscillations during Incidental Encoding Predict Subsequent Memory for New "Foil" Information.

PubMed

Vogelsang, David A; Gruber, Matthias; Bergström, Zara M; Ranganath, Charan; Simons, Jon S

2018-05-01

People can employ adaptive strategies to increase the likelihood that previously encoded information will be successfully retrieved. One such strategy is to constrain retrieval toward relevant information by reimplementing the neurocognitive processes that were engaged during encoding. Using EEG, we examined the temporal dynamics with which constraining retrieval toward semantic versus nonsemantic information affects the processing of new "foil" information encountered during a memory test. Time-frequency analysis of EEG data acquired during an initial study phase revealed that semantic compared with nonsemantic processing was associated with alpha decreases in a left frontal electrode cluster from around 600 msec after stimulus onset. Successful encoding of semantic versus nonsemantic foils during a subsequent memory test was related to decreases in alpha oscillatory activity in the same left frontal electrode cluster, which emerged relatively late in the trial at around 1000-1600 msec after stimulus onset. Across participants, left frontal alpha power elicited by semantic processing during the study phase correlated significantly with left frontal alpha power associated with semantic foil encoding during the memory test. Furthermore, larger left frontal alpha power decreases elicited by semantic foil encoding during the memory test predicted better subsequent semantic foil recognition in an additional surprise foil memory test, although this effect did not reach significance. These findings indicate that constraining retrieval toward semantic information involves reimplementing semantic encoding operations that are mediated by alpha oscillations and that such reimplementation occurs at a late stage of memory retrieval, perhaps reflecting additional monitoring processes.

Differential pattern of semantic memory organization between bipolar I and II disorders.

PubMed

Chang, Jae Seung; Choi, Sungwon; Ha, Kyooseob; Ha, Tae Hyon; Cho, Hyun Sang; Choi, Jung Eun; Cha, Boseok; Moon, Eunsoo

2011-06-01

Semantic cognition is one of the key factors in psychosocial functioning. The aim of this study was to explore the differences in pattern of semantic memory organization between euthymic patients with bipolar I and II disorders using the category fluency task. Study participants included 23 euthymic subjects with bipolar I disorder, 23 matched euthymic subjects with bipolar II disorder and 23 matched control subjects. All participants were assessed for verbal learning, recall, learning strategies, and fluency. The combined methods of hierarchical clustering and multidimensional scaling were used to compare the pattern of semantic memory organization among the three groups. Quantitative measures of verbal learning, recall, learning strategies, and fluency did not differ between the three groups. A two-cluster structure of semantic memory organization was identified for the three groups. Semantic structure was more disorganized in the bipolar I disorder group compared to the bipolar II disorder. In addition, patients with bipolar II disorder used less elaborate strategies of semantic memory organization than those of controls. Compared to healthy controls, strategies for categorization in semantic memory appear to be less knowledge-based in patients with bipolar disorders. A differential pattern of semantic memory organization between bipolar I and II disorders indicates a higher risk of cognitive abnormalities in patients with bipolar I disorder compared to patients with bipolar II disorder. Exploring qualitative nature of neuropsychological domains may provide an explanatory insight into the characteristic behaviors of patients with bipolar disorders. Copyright © 2011 Elsevier Inc. All rights reserved.

Remembering episodic memories is not necessary for forgetting of negative words: Semantic retrieval can cause forgetting of negative words.

PubMed

Kobayashi, Masanori; Tanno, Yoshihiko

2015-06-01

Retrieval of a memory can induce forgetting of other related memories, which is known as retrieval-induced forgetting. Although most studies have investigated retrieval-induced forgetting by remembering episodic memories, this also can occur by remembering semantic memories. The present study shows that retrieval of semantic memories can lead to forgetting of negative words. In two experiments, participants learned words and then engaged in retrieval practice where they were asked to recall words related to the learned words from semantic memory. Finally, participants completed a stem-cued recall test for the learned words. The results showed forgetting of neutral and negative words, which was characteristic of semantic retrieval-induced forgetting. A certain degree of overlapping features, except same learning episode, is sufficient to cause retrieval-induced forgetting of negative words. Given the present results, we conclude that retrieval-induced forgetting of negative words does not require recollection of episodic memories.

Semantic memory retrieval circuit: role of pre-SMA, caudate, and thalamus.

PubMed

Hart, John; Maguire, Mandy J; Motes, Michael; Mudar, Raksha Anand; Chiang, Hsueh-Sheng; Womack, Kyle B; Kraut, Michael A

2013-07-01

We propose that pre-supplementary motor area (pre-SMA)-thalamic interactions govern processes fundamental to semantic retrieval of an integrated object memory. At the onset of semantic retrieval, pre-SMA initiates electrical interactions between multiple cortical regions associated with semantic memory subsystems encodings as indexed by an increase in theta-band EEG power. This starts between 100-150 ms after stimulus presentation and is sustained throughout the task. We posit that this activity represents initiation of the object memory search, which continues in searching for an object memory. When the correct memory is retrieved, there is a high beta-band EEG power increase, which reflects communication between pre-SMA and thalamus, designates the end of the search process and resultant in object retrieval from multiple semantic memory subsystems. This high beta signal is also detected in cortical regions. This circuit is modulated by the caudate nuclei to facilitate correct and suppress incorrect target memories. Copyright © 2012 Elsevier Inc. All rights reserved.

Generation and context memory.

PubMed

Mulligan, Neil W; Lozito, Jeffrey P; Rosner, Zachary A

2006-07-01

Generation enhances memory for occurrence but may not enhance other aspects of memory. The present study further delineates the negative generation effect in context memory reported in N. W. Mulligan (2004). First, the negative generation effect occurred for perceptual attributes of the target item (its color and font) but not for extratarget aspects of context (location and background color). Second, nonvisual generation tasks with either semantic or nonsemantic generation rules (antonym and rhyme generation, respectively) produced the same pattern of results. In contrast, a visual (or data-driven) generation task (letter transposition) did not disrupt context memory for color. Third, generating nonwords produced no effect on item memory but persisted in producing a negative effect on context memory for target attributes, implying that (a) the negative generation effect in context memory is not mediated by semantic encoding, and (b) the negative effect on context memory can be dissociated from the positive effect on item memory. The results are interpreted in terms of the processing account of generation. The original, perceptual-conceptual version of this account is too narrow, but a modified processing account, based on a more generic visual versus nonvisual processing distinction, accommodates the results. Copyright 2006 APA, all rights reserved.

Semantic memory assessment in 15 patients with amyotrophic lateral sclerosis.

PubMed

Hervieu-Bègue, M; Rouaud, O; Graule Petot, A; Catteau, A; Giroud, M

2016-01-01

A total of 30 to 50% of amyotrophic lateral sclerosis patients suffer from cognitive disorders. The aim of the study is to characterize these disorders and to assess semantic memory in non-demented ALS patients. The secondary aim is to look for a link between disease type and neuropsychological characteristics. Patients were followed in an ALS center in Dijon. The following neuropsychological tests were used in this study: Folstein test, BREF test, verbal fluency, Isaac test, GRESEM test and TOP 30 test. Fifteen ALS patients were included. Nine of them (60%) were suffering from a semantic memory disorder. There was no correlation between ALS characteristics and the semantic memory disorder. This is the first study to reveal a semantic memory disorder in ALS. This result accentuates the hypothesis that ALS and semantic dementia are two phenotypes of the same degenerative process linked to TDP 43 proteinopathy. Copyright © 2016. Published by Elsevier Masson SAS.

School-aged children can benefit from audiovisual semantic congruency during memory encoding.

PubMed

Heikkilä, Jenni; Tiippana, Kaisa

2016-05-01

Although we live in a multisensory world, children's memory has been usually studied concentrating on only one sensory modality at a time. In this study, we investigated how audiovisual encoding affects recognition memory. Children (n = 114) from three age groups (8, 10 and 12 years) memorized auditory or visual stimuli presented with a semantically congruent, incongruent or non-semantic stimulus in the other modality during encoding. Subsequent recognition memory performance was better for auditory or visual stimuli initially presented together with a semantically congruent stimulus in the other modality than for stimuli accompanied by a non-semantic stimulus in the other modality. This congruency effect was observed for pictures presented with sounds, for sounds presented with pictures, for spoken words presented with pictures and for written words presented with spoken words. The present results show that semantically congruent multisensory experiences during encoding can improve memory performance in school-aged children.

Personal semantic and episodic autobiographical memories in Korsakoff syndrome: A comparison of interview methods.

PubMed

Rensen, Yvonne C M; Kessels, Roy P C; Migo, Ellen M; Wester, Arie J; Eling, Paul A T M; Kopelman, Michael D

2017-08-01

The temporal gradient in patients with Korsakoff's syndrome has been of particular interest in the literature, as many studies have found evidence for a steep temporal gradient, but others have observed more uniform remote memory impairment across all past time periods. Inconsistencies might be the result of the nature of remote memory impairment under study (i.e., nonpersonal or autobiographical memory) and of methodological differences in the examination of remote memory loss. The aim of this study was to examine whether differences between autobiographical memory interview (AMI) and autobiographical interview (AI) procedures influence the presence of a temporal gradient in semantic and episodic autobiographical memory in Korsakoff patients. The procedure used in the present study combined the AMI and AI into one study session. We compared the performance of 20 patients with Korsakoff's syndrome and 27 healthy controls. First, participants were asked to recall knowledge from different life periods. Second, participants were asked to recall memories from five life periods. Thirdly, participants were asked to rate their subjective experience of each event recalled on a 5-point scale. Finally, we analyzed the findings in terms of all the memories recalled versus the first memory from each life-period only. Both the AMI and the AI showed a temporally graded retrograde amnesia in the Korsakoff patients for personal semantic and episodic autobiographical memories. The pattern of amnesia in Korsakoff patients was not affected by examining only one event per life-period. Subjective ratings of recalled memories were largely comparable between the groups. The findings were generally consistent across the AMI and AI. Varying the number of events did not affect the pattern of the gradient. Hence, the temporal gradient in Korsakoff patients is not an artefact of either the AMI or the AI method.

Episodic, semantic and procedural memory in a case of amnesia at an early age.

PubMed

Ostergaard, A L

1987-01-01

The patient C.C. developed an amnesic syndrome at the age of 10 yr. Like adult amnesics, C.C. demonstrated impaired episodic memory for both verbal and visual materials although immediate memory span was spared. However, striking deficits were also observed on a wide variety of semantic memory tasks, including reading vocabulary and verbal fluency tests, semantic classification and lexical decision tasks and tests of verbal intelligence. On the other hand, C.C. showed normal learning and retention of two procedural tasks. It was argued that this evidence is inconsistent with the view that the amnesic syndrome represents a selective defect of episodic memory that leaves semantic memory relatively unaffected.

Musical and Verbal Memory in Alzheimer's Disease: A Study of Long-Term and Short-Term Memory

ERIC Educational Resources Information Center

Menard, Marie-Claude; Belleville, Sylvie

2009-01-01

Musical memory was tested in Alzheimer patients and in healthy older adults using long-term and short-term memory tasks. Long-term memory (LTM) was tested with a recognition procedure using unfamiliar melodies. Short-term memory (STM) was evaluated with same/different judgment tasks on short series of notes. Musical memory was compared to verbal…

Correlation between Gray/White Matter Volume and Cognition in Healthy Elderly People

ERIC Educational Resources Information Center

Taki, Yasuyuki; Kinomura, Shigeo; Sato, Kazunori; Goto, Ryoi; Wu, Kai; Kawashima, Ryuta; Fukuda, Hiroshi

2011-01-01

This study applied volumetric analysis and voxel-based morphometry (VBM) of brain magnetic resonance (MR) images to assess whether correlations exist between global and regional gray/white matter volume and the cognitive functions of semantic memory and short-term memory, which are relatively well preserved with aging, using MR image data from 109…

Learning to Read in Arabic: Reading, Syntactic, Orthographic and Working Memory Skills in Normally Achieving and Poor Arabic Readers.

ERIC Educational Resources Information Center

Abu-Rabia, Salim

1995-01-01

Examines relationships between phonological skills and reading in 143 Arab children in Arab villages of central Israel. Finds that a word recognition test was highly correlated with phonological skills, semantic processing, syntactic knowledge, and short-term memory, and that poor readers significantly lagged in skill development. Discusses…

Longitudinal Study of a Novel, Performance-based Measure of Daily Function

DTIC Science & Technology

2016-06-01

have functional impairments, and healthy age matched controls on the UPSA, as well as measures of cognition (e.g., episodic memory , semantic memory ...controls on the UPSA, as well as measures of cognition (e.g., episodic memory , semantic memory , executive function, speed). We found that patients with...diagnosis have functional impairments, and healthy age matched controls on the UPSA, as well as measures of cognition (e.g., episodic memory , semantic

A Functional Examination of Intermediate Cognitive Processes.

DTIC Science & Technology

1986-01-01

memory ) and a body of accumulated information referred to as " semantic memory ". In contrast with episodic memory (which most psychological experiments...referents of input signals. (p. 386) But as Eysenck (1984) points out, there is "no precise dividing line" betveen episodic and semantic memory and although...involve), Tulving suggests that semantic memory is the more crucial to 5. .P, 31 performing everyday tasks: It is a mental thesaurus, the

The role of sleep spindles and slow-wave activity in integrating new information in semantic memory.

PubMed

Tamminen, Jakke; Lambon Ralph, Matthew A; Lewis, Penelope A

2013-09-25

Assimilating new information into existing knowledge is a fundamental part of consolidating new memories and allowing them to guide behavior optimally and is vital for conceptual knowledge (semantic memory), which is accrued over many years. Sleep is important for memory consolidation, but its impact upon assimilation of new information into existing semantic knowledge has received minimal examination. Here, we examined the integration process by training human participants on novel words with meanings that fell into densely or sparsely populated areas of semantic memory in two separate sessions. Overnight sleep was polysomnographically monitored after each training session and recall was tested immediately after training, after a night of sleep, and 1 week later. Results showed that participants learned equal numbers of both word types, thus equating amount and difficulty of learning across the conditions. Measures of word recognition speed showed a disadvantage for novel words in dense semantic neighborhoods, presumably due to interference from many semantically related concepts, suggesting that the novel words had been successfully integrated into semantic memory. Most critically, semantic neighborhood density influenced sleep architecture, with participants exhibiting more sleep spindles and slow-wave activity after learning the sparse compared with the dense neighborhood words. These findings provide the first evidence that spindles and slow-wave activity mediate integration of new information into existing semantic networks.

Musical practice and cognitive aging: two cross-sectional studies point to phonemic fluency as a potential candidate for a use-dependent adaptation.

PubMed

Fauvel, Baptiste; Groussard, Mathilde; Mutlu, Justine; Arenaza-Urquijo, Eider M; Eustache, Francis; Desgranges, Béatrice; Platel, Hervé

2014-01-01

Because of permanent use-dependent brain plasticity, all lifelong individuals' experiences are believed to influence the cognitive aging quality. In older individuals, both former and current musical practices have been associated with better verbal skills, visual memory, processing speed, and planning function. This work sought for an interaction between musical practice and cognitive aging by comparing musician and non-musician individuals for two lifetime periods (middle and late adulthood). Long-term memory, auditory-verbal short-term memory, processing speed, non-verbal reasoning, and verbal fluencies were assessed. In Study 1, measures of processing speed and auditory-verbal short-term memory were significantly better performed by musicians compared with controls, but both groups displayed the same age-related differences. For verbal fluencies, musicians scored higher than controls and displayed different age effects. In Study 2, we found that lifetime period at training onset (childhood vs. adulthood) was associated with phonemic, but not semantic, fluency performances (musicians who had started to practice in adulthood did not perform better on phonemic fluency than non-musicians). Current frequency of training did not account for musicians' scores on either of these two measures. These patterns of results are discussed by setting the hypothesis of a transformative effect of musical practice against a non-causal explanation.

Supporting the self-concept with memory: insight from amnesia.

PubMed

Grilli, Matthew D; Verfaellie, Mieke

2015-12-01

We investigated the extent to which personal semantic memory supports the self-concept in individuals with medial temporal lobe amnesia and healthy adults. Participants completed eight 'I Am' self-statements. For each of the four highest ranked self-statements, participants completed an open-ended narrative task, during which they provided supporting information indicating why the I Am statement was considered self-descriptive. Participants then completed an episodic probe task, during which they attempted to retrieve six episodic memories for each of these self-statements. Supporting information was scored as episodic, personal semantic or general semantic. In the narrative task, personal semantic memory predominated as self-supporting information in both groups. The amnesic participants generated fewer personal semantic memories than controls to support their self-statements, a deficit that was more pronounced for trait relative to role self-statements. In the episodic probe task, the controls primarily generated unique event memories, but the amnesic participants did not. These findings demonstrate that personal semantic memory, in particular autobiographical fact knowledge, plays a critical role in supporting the self-concept, regardless of the accessibility of episodic memories, and they highlight potential differences in the way traits and roles are supported by personal memory. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

The role of working memory and divided attention in metaphor interpretation.

PubMed

Iskandar, Sam; Baird, Anne D

2014-10-01

Although several types of figurative language exist, neuropsychological tests of non-literal language have focused on proverbs. Metaphors in the form X is (a) Y (e.g., The body's immunological response is a battle against disease.) place a lower demand on language skills and are more easily manipulated for novelty than proverbs. Forty healthy participants completed the Metaphor Interpretation Test (developed by the authors). The task includes 20 items chosen from a list of metaphors that were rated on several scales (e.g. imagery, aptness) in a study by Katz et al. (Metaphor Symb Act 3(4):191-214, 1988). Participants were asked to rate the familiarity and provide an explanation of each metaphor. A scoring system was developed to categorize answers into: abstract complete (AC), abstract partial (AP), concrete (CT), and other/unrelated (OT) types. Participants also completed short-term memory and divided attention tests. Overall, participants produced 56 % AC, 25.38 % AP, 7.88 % CT, and 10.88 % OT responses. It was found that a measure of verbal short-term memory span was the best predictor of performance on this task (adjusted R(2) = .369). It appears that short-term memory span, not working memory or divided attention, contributes most to providing abstract responses in explaining metaphors. This is in line with the idea that when one accesses the semantic network associated with a novel metaphor, one must hold this information in mind long enough to search for and link similar cognitive networks.

Episodic and Semantic Autobiographical Memory and Everyday Memory during Late Childhood and Early Adolescence

PubMed Central

Willoughby, Karen A.; Desrocher, Mary; Levine, Brian; Rovet, Joanne F.

2012-01-01

Few studies have examined both episodic and semantic autobiographical memory (AM) performance during late childhood and early adolescence. Using the newly developed Children’s Autobiographical Interview (CAI), the present study examined the effects of age and sex on episodic and semantic AM and everyday memory in 182 children and adolescents. Results indicated that episodic and semantic AM both improved between 8 and 16 years of age; however, age-related changes were larger for episodic AM than for semantic AM. In addition, females were found to recall more episodic AM details, but not more semantic AM details, than males. Importantly, this sex difference in episodic AM recall was attenuated under conditions of high retrieval support (i.e., the use of probing questions). The ability to clearly visualize past events at the time of recollection was related to children’s episodic AM recall performance, particularly the retrieval of perceptual details. Finally, similar age and sex effects were found between episodic AM and everyday memory ability (e.g., memory for everyday activities). More specifically, older participants and females exhibited better episodic AM and everyday memory performance than younger participants and males. Overall, the present study provides important new insight into both episodic and semantic AM performance, as well as the relation between episodic AM and everyday memory, during late childhood and adolescence. PMID:22403560

Episodic and Semantic Autobiographical Memory and Everyday Memory during Late Childhood and Early Adolescence.

PubMed

Willoughby, Karen A; Desrocher, Mary; Levine, Brian; Rovet, Joanne F

2012-01-01

Few studies have examined both episodic and semantic autobiographical memory (AM) performance during late childhood and early adolescence. Using the newly developed Children's Autobiographical Interview (CAI), the present study examined the effects of age and sex on episodic and semantic AM and everyday memory in 182 children and adolescents. Results indicated that episodic and semantic AM both improved between 8 and 16 years of age; however, age-related changes were larger for episodic AM than for semantic AM. In addition, females were found to recall more episodic AM details, but not more semantic AM details, than males. Importantly, this sex difference in episodic AM recall was attenuated under conditions of high retrieval support (i.e., the use of probing questions). The ability to clearly visualize past events at the time of recollection was related to children's episodic AM recall performance, particularly the retrieval of perceptual details. Finally, similar age and sex effects were found between episodic AM and everyday memory ability (e.g., memory for everyday activities). More specifically, older participants and females exhibited better episodic AM and everyday memory performance than younger participants and males. Overall, the present study provides important new insight into both episodic and semantic AM performance, as well as the relation between episodic AM and everyday memory, during late childhood and adolescence.

Personal semantic memory: insights from neuropsychological research on amnesia.

PubMed

Grilli, Matthew D; Verfaellie, Mieke

2014-08-01

This paper provides insight into the cognitive and neural mechanisms of personal semantic memory, knowledge that is specific and unique to individuals, by reviewing neuropsychological research on stable amnesia secondary to medial temporal lobe damage. The results reveal that personal semantic memory does not depend on a unitary set of cognitive and neural mechanisms. Findings show that autobiographical fact knowledge reflects an experience-near type of personal semantic memory that relies on the medial temporal lobe for retrieval, albeit less so than personal episodic memory. Additional evidence demonstrates that new autobiographical fact learning likely relies on the medial temporal lobe, but the extent to which remains unclear. Other findings show that retrieval of personal traits/roles and new learning of personal traits/roles and thoughts/beliefs are independent of the medial temporal lobe and thus may represent highly conceptual types of personal semantic memory that are stored in the neocortex. Published by Elsevier Ltd.

The impact of semantic impairment on word stem completion in Alzheimer's disease.

PubMed

Beauregard, M; Chertkow, H; Gold, D; Bergman, S

2001-01-01

Both the extent of semantic memory impairment and the level of processing attained during encoding might constitute critical factors in determining the amount of word-stem completion (WSC) priming encountered in Alzheimer's disease (AD) subjects. We investigated the impact of varying encoding level in AD and elderly normal subjects, using a set of stimuli ranked as "intact" or "degraded" in terms of each subject's semantic knowledge on probe questions. For both shallow and deep encoding conditions, overall priming in the two subject groups was equivalent. However, for the deep encoding condition, consisting of a semantic judgment task performed on each target word, the priming effect noted in AD subjects was significantly smaller for semantically degraded items than for semantically intact items. Results indicate that the degree of semantic impairment represents one important variable affecting the amount of WSC priming which results when deep encoding procedures are used at study.

The Deese-Roediger-McDermott (DRM) Task: A Simple Cognitive Paradigm to Investigate False Memories in the Laboratory.

PubMed

Pardilla-Delgado, Enmanuelle; Payne, Jessica D

2017-01-31

The Deese, Roediger and McDermott (DRM) task is a false memory paradigm in which subjects are presented with lists of semantically related words (e.g., nurse, hospital, etc.) at encoding. After a delay, subjects are asked to recall or recognize these words. In the recognition memory version of the task, subjects are asked whether they remember previously presented words, as well as related (but never presented) critical lure words ('doctor'). Typically, the critical word is recognized with high probability and confidence. This false memory effect has been robustly demonstrated across short (e.g., immediate, 20 min) and long (e.g., 1, 7, 60 d) delays between encoding and memory testing. A strength of using this task to study false memory is its simplicity and short duration. If encoding and retrieval components of the task occur in the same session, the entire task can take as little as 2 - 30 min. However, although the DRM task is widely considered a 'false memory' paradigm, some researchers consider DRM illusions to be based on the activation of semantic memory networks in the brain, and argue that such semantic gist-based false memory errors may actually be useful in some scenarios (e.g., remembering the forest for the trees; remembering that a word list was about "doctors", even though the actual word "doctor" was never presented for study). Remembering the gist of experience (instead of or along with individual details) is arguably an adaptive process and this task has provided a great deal of knowledge about the constructive, adaptive nature of memory. Therefore, researchers should use caution when discussing the overall reach and implications of their experiments when using this task to study 'false memory', as DRM memory errors may not adequately reflect false memories in the real world, such as false memory in eyewitness testimony, or false memories of sexual abuse.

Long-Term Memory Performance in Adult ADHD.

PubMed

Skodzik, Timo; Holling, Heinz; Pedersen, Anya

2017-02-01

Memory problems are a frequently reported symptom in adult ADHD, and it is well-documented that adults with ADHD perform poorly on long-term memory tests. However, the cause of this effect is still controversial. The present meta-analysis examined underlying mechanisms that may lead to long-term memory impairments in adult ADHD. We performed separate meta-analyses of measures of memory acquisition and long-term memory using both verbal and visual memory tests. In addition, the influence of potential moderator variables was examined. Adults with ADHD performed significantly worse than controls on verbal but not on visual long-term memory and memory acquisition subtests. The long-term memory deficit was strongly statistically related to the memory acquisition deficit. In contrast, no retrieval problems were observable. Our results suggest that memory deficits in adult ADHD reflect a learning deficit induced at the stage of encoding. Implications for clinical and research settings are presented.

Individual differences in algebraic cognition: Relation to the approximate number and semantic memory systems.

PubMed

Geary, David C; Hoard, Mary K; Nugent, Lara; Rouder, Jeffrey N

2015-12-01

The relation between performance on measures of algebraic cognition and acuity of the approximate number system (ANS) and memory for addition facts was assessed for 171 ninth graders (92 girls) while controlling for parental education, sex, reading achievement, speed of numeral processing, fluency of symbolic number processing, intelligence, and the central executive component of working memory. The algebraic tasks assessed accuracy in placing x,y pairs in the coordinate plane, speed and accuracy of expression evaluation, and schema memory for algebra equations. ANS acuity was related to accuracy of placements in the coordinate plane and expression evaluation but not to schema memory. Frequency of fact retrieval errors was related to schema memory but not to coordinate plane or expression evaluation accuracy. The results suggest that the ANS may contribute to or be influenced by spatial-numerical and numerical-only quantity judgments in algebraic contexts, whereas difficulties in committing addition facts to long-term memory may presage slow formation of memories for the basic structure of algebra equations. More generally, the results suggest that different brain and cognitive systems are engaged during the learning of different components of algebraic competence while controlling for demographic and domain general abilities. Copyright © 2015 Elsevier Inc. All rights reserved.

HDAC inhibition modulates hippocampus-dependent long-term memory for object location in a CBP-dependent manner

PubMed Central

Haettig, Jakob; Stefanko, Daniel P.; Multani, Monica L.; Figueroa, Dario X.; McQuown, Susan C.; Wood, Marcelo A.

2011-01-01

Transcription of genes required for long-term memory not only involves transcription factors, but also enzymatic protein complexes that modify chromatin structure. Chromatin-modifying enzymes, such as the histone acetyltransferase (HAT) CREB (cyclic-AMP response element binding) binding protein (CBP), are pivotal for the transcriptional regulation required for long-term memory. Several studies have shown that CBP and histone acetylation are necessary for hippocampus-dependent long-term memory and hippocampal long-term potentiation (LTP). Importantly, every genetically modified Cbp mutant mouse exhibits long-term memory impairments in object recognition. However, the role of the hippocampus in object recognition is controversial. To better understand how chromatin-modifying enzymes modulate long-term memory for object recognition, we first examined the role of the hippocampus in retrieval of long-term memory for object recognition or object location. Muscimol inactivation of the dorsal hippocampus prior to retrieval had no effect on long-term memory for object recognition, but completely blocked long-term memory for object location. This was consistent with experiments showing that muscimol inactivation of the hippocampus had no effect on long-term memory for the object itself, supporting the idea that the hippocampus encodes spatial information about an object (such as location or context), whereas cortical areas (such as the perirhinal or insular cortex) encode information about the object itself. Using location-dependent object recognition tasks that engage the hippocampus, we demonstrate that CBP is essential for the modulation of long-term memory via HDAC inhibition. Together, these results indicate that HDAC inhibition modulates memory in the hippocampus via CBP and that different brain regions utilize different chromatin-modifying enzymes to regulate learning and memory. PMID:21224411

Getting connected: Both associative and semantic links structure semantic memory for newly learned persons.

PubMed

Wiese, Holger; Schweinberger, Stefan R

2015-01-01

The present study examined whether semantic memory for newly learned people is structured by visual co-occurrence, shared semantics, or both. Participants were trained with pairs of simultaneously presented (i.e., co-occurring) preexperimentally unfamiliar faces, which either did or did not share additionally provided semantic information (occupation, place of living, etc.). Semantic information could also be shared between faces that did not co-occur. A subsequent priming experiment revealed faster responses for both co-occurrence/no shared semantics and no co-occurrence/shared semantics conditions, than for an unrelated condition. Strikingly, priming was strongest in the co-occurrence/shared semantics condition, suggesting additive effects of these factors. Additional analysis of event-related brain potentials yielded priming in the N400 component only for combined effects of visual co-occurrence and shared semantics, with more positive amplitudes in this than in the unrelated condition. Overall, these findings suggest that both semantic relatedness and visual co-occurrence are important when novel information is integrated into person-related semantic memory.

Overlap in the functional neural systems involved in semantic and episodic memory retrieval.

PubMed

Rajah, M N; McIntosh, A R

2005-03-01

Neuroimaging and neuropsychological data suggest that episodic and semantic memory may be mediated by distinct neural systems. However, an alternative perspective is that episodic and semantic memory represent different modes of processing within a single declarative memory system. To examine whether the multiple or the unitary system view better represents the data we conducted a network analysis using multivariate partial least squares (PLS ) activation analysis followed by covariance structural equation modeling (SEM) of positron emission tomography data obtained while healthy adults performed episodic and semantic verbal retrieval tasks. It is argued that if performance of episodic and semantic retrieval tasks are mediated by different memory systems, then there should differences in both regional activations and interregional correlations related to each type of retrieval task, respectively. The PLS results identified brain regions that were differentially active during episodic retrieval versus semantic retrieval. Regions that showed maximal differences in regional activity between episodic retrieval tasks were used to construct separate functional models for episodic and semantic retrieval. Omnibus tests of these functional models failed to find a significant difference across tasks for both functional models. The pattern of path coefficients for the episodic retrieval model were not different across tasks, nor were the path coefficients for the semantic retrieval model. The SEM results suggest that the same memory network/system was engaged across tasks, given the similarities in path coefficients. Therefore, activation differences between episodic and semantic retrieval may ref lect variation along a continuum of processing during task performance within the context of a single memory system.

Insights from child development on the relationship between episodic and semantic memory.

PubMed

Robertson, Erin K; Köhler, Stefan

2007-11-05

The present study was motivated by a recent controversy in the neuropsychological literature on semantic dementia as to whether episodic encoding requires semantic processing or whether it can proceed solely based on perceptual processing. We addressed this issue by examining the effect of age-related limitations in semantic competency on episodic memory in 4-6-year-old children (n=67). We administered three different forced-choice recognition memory tests for pictures previously encountered in a single study episode. The tests varied in the degree to which access to semantically encoded information was required at retrieval. Semantic competency predicted recognition performance regardless of whether access to semantic information was required. A direct relation between picture naming at encoding and subsequent recognition was also found for all tests. Our findings emphasize the importance of semantic encoding processes even in retrieval situations that purportedly do not require access to semantic information. They also highlight the importance of testing neuropsychological models of memory in different populations, healthy and brain damaged, at both ends of the developmental continuum.

Semantic Processing Impairment in Patients with Temporal Lobe Epilepsy

PubMed Central

Jaimes-Bautista, Amanda G.; Rodríguez-Camacho, Mario; Martínez-Juárez, Iris E.; Rodríguez-Agudelo, Yaneth

2015-01-01

The impairment in episodic memory system is the best-known cognitive deficit in patients with temporal lobe epilepsy (TLE). Recent studies have shown evidence of semantic disorders, but they have been less studied than episodic memory. The semantic dysfunction in TLE has various cognitive manifestations, such as the presence of language disorders characterized by defects in naming, verbal fluency, or remote semantic information retrieval, which affects the ability of patients to interact with their surroundings. This paper is a review of recent research about the consequences of TLE on semantic processing, considering neuropsychological, electrophysiological, and neuroimaging findings, as well as the functional role of the hippocampus in semantic processing. The evidence from these studies shows disturbance of semantic memory in patients with TLE and supports the theory of declarative memory of the hippocampus. Functional neuroimaging studies show an inefficient compensatory functional reorganization of semantic networks and electrophysiological studies show a lack of N400 effect that could indicate that the deficit in semantic processing in patients with TLE could be due to a failure in the mechanisms of automatic access to lexicon. PMID:26257956

Serial-position effects for items and relations in short-term memory.

PubMed

Jones, Tim; Oberauer, Klaus

2013-04-01

Two experiments used immediate probed recall of words to investigate serial-position effects. Item memory was tested through probing with a semantic category. Relation memory was tested through probing with the word's spatial location of presentation. Input order and output order were deconfounded by presenting and probing items in different orders. Primacy and recency effects over input position were found for both item memory and relation memory. Both item and relation memory declined over output position. The finding of a U-shaped input position function for item memory rules out an explanation purely in terms of positional confusions (e.g., edge effects). Either these serial-position effects arise from variations in the intrinsic memory strength of the items, or they arise from variations in the strength of item-position bindings, together with retrieval by scanning.

Modulation of alpha oscillations is required for the suppression of semantic interference.

PubMed

Melnik, Natalia; Mapelli, Igor; Özkurt, Tolga Esat

2017-10-01

Recent findings on alpha band oscillations suggest their important role in memory consolidation and suppression of external distractors such as environmental noise. However, less attention was given to the phenomenon of internal distracting information being solely inherent to the stimuli content. Human memory may be prone to internal distractions caused by semantic relatedness between the meaning of words (e.g., atom, neutron, nucleus, etc.) to be encoded, i.e., semantic interference. Our study investigates the brain oscillatory dynamics behind the semantic interference phenomenon, whose possible outcome is known as false memories. In this direction, Deese-Roediger-McDermott word lists were appropriated for a modified Sternberg paradigm in auditory modality. Participants received semantically related and unrelated word lists via headphones while EEG data were acquired. Semantic interference triggered the false memory rates to be higher than those of other types of memory errors. Analysis demonstrated that the upper part of alpha band (∼10-12Hz) power decreases on parieto-occipital channels in the retention interval, prior to the probe item for semantically related condition. Our study elucidates the oscillatory mechanisms behind semantic interference by relying on alpha functional inhibition theory. Copyright © 2017 Elsevier Inc. All rights reserved.

Fluoxetine Inhibits Natural Decay of Long-Term Memory via Akt/GSK-3β Signaling.

PubMed

Yi, Jee Hyun; Zhang, JiaBao; Ko, Sang Yoon; Kwon, Huiyoung; Jeon, Se Jin; Park, Se Jin; Jung, Jiwook; Kim, Byung C; Lee, Young Choon; Kim, Dong Hyun; Ryu, Jong Hoon

2018-02-09

Understanding the mechanisms underlying the natural decay of long-term memory can help us find means of extending the duration of long-term memory. However, the neurobiological processes involved in the decay of long-term memory are poorly understood. In the present study, we examined the effect of acute and chronic treatment of fluoxetine on natural decay of long-term memory and the possible mechanism. Late administration of fluoxetine prolonged the persistence of long-term memory in mice, as demonstrated by object location recognition and Barnes maze tests. Fluoxetine altered Akt/glycogen synthase kinase-3β (GSK-3β)/β-catenin signaling in the hippocampus. Late short- and long-term pharmacological inhibition of GSK-3β mimicked the effect of fluoxetine on memory persistence. Pharmacological inhibition of Akt blocked the effect of fluoxetine on memory persistence. Finally, late infusion of fluoxetine increased hippocampal long-term potentiation (LTP) and pharmacological inhibition of GSK-3β blocked the natural decline in LTP. These results demonstrate that GSK-3β might be a key molecule in memory decay process, and fluoxetine extends the period of long-term memory maintenance via Akt/GSK-3β signaling.

One declarative memory system or two? The relationship between episodic and semantic memory in children with temporal lobe epilepsy.

PubMed

Smith, Mary Lou; Lah, Suncica

2011-09-01

This study explored verbal semantic and episodic memory in children with unilateral temporal lobe epilepsy to determine whether they had impairments in both or only 1 aspect of memory, and to examine relations between performance in the 2 domains. Sixty-six children and adolescents (37 with seizures of left temporal lobe onset, 29 with right-sided onset) were given 4 tasks assessing different aspects of semantic memory (picture naming, fluency, knowledge of facts, knowledge of word meanings) and 2 episodic memory tasks (story recall, word list recall). High rates of impairments were observed across tasks, and no differences were found related to the laterality of the seizures. Individual patient analyses showed that there was a double dissociation between the 2 aspects of memory in that some children were impaired on episodic but not semantic memory, whereas others showed intact episodic but impaired semantic memory. This double dissociation suggests that these 2 memory systems may develop independently in the context of temporal lobe pathology, perhaps related to differential effects of dysfunction in the lateral and mesial temporal lobe structures. PsycINFO Database Record (c) 2011 APA, all rights reserved.

Goal-directed mechanisms that constrain retrieval predict subsequent memory for new "foil" information.

PubMed

Vogelsang, David A; Bonnici, Heidi M; Bergström, Zara M; Ranganath, Charan; Simons, Jon S

2016-08-01

To remember a previous event, it is often helpful to use goal-directed control processes to constrain what comes to mind during retrieval. Behavioral studies have demonstrated that incidental learning of new "foil" words in a recognition test is superior if the participant is trying to remember studied items that were semantically encoded compared to items that were non-semantically encoded. Here, we applied subsequent memory analysis to fMRI data to understand the neural mechanisms underlying the "foil effect". Participants encoded information during deep semantic and shallow non-semantic tasks and were tested in a subsequent blocked memory task to examine how orienting retrieval towards different types of information influences the incidental encoding of new words presented as foils during the memory test phase. To assess memory for foils, participants performed a further surprise old/new recognition test involving foil words that were encountered during the previous memory test blocks as well as completely new words. Subsequent memory effects, distinguishing successful versus unsuccessful incidental encoding of foils, were observed in regions that included the left inferior frontal gyrus and posterior parietal cortex. The left inferior frontal gyrus exhibited disproportionately larger subsequent memory effects for semantic than non-semantic foils, and significant overlap in activity during semantic, but not non-semantic, initial encoding and foil encoding. The results suggest that orienting retrieval towards different types of foils involves re-implementing the neurocognitive processes that were involved during initial encoding. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Mathematical Logic in the Human Brain: Semantics

PubMed Central

Friedrich, Roland M.; Friederici, Angela D.

2013-01-01

As a higher cognitive function in humans, mathematics is supported by parietal and prefrontal brain regions. Here, we give an integrative account of the role of the different brain systems in processing the semantics of mathematical logic from the perspective of macroscopic polysynaptic networks. By comparing algebraic and arithmetic expressions of identical underlying structure, we show how the different subparts of a fronto-parietal network are modulated by the semantic domain, over which the mathematical formulae are interpreted. Within this network, the prefrontal cortex represents a system that hosts three major components, namely, control, arithmetic-logic, and short-term memory. This prefrontal system operates on data fed to it by two other systems: a premotor-parietal top-down system that updates and transforms (external) data into an internal format, and a hippocampal bottom-up system that either detects novel information or serves as an access device to memory for previously acquired knowledge. PMID:23301101

Mathematical logic in the human brain: semantics.

PubMed

Friedrich, Roland M; Friederici, Angela D

2013-01-01

As a higher cognitive function in humans, mathematics is supported by parietal and prefrontal brain regions. Here, we give an integrative account of the role of the different brain systems in processing the semantics of mathematical logic from the perspective of macroscopic polysynaptic networks. By comparing algebraic and arithmetic expressions of identical underlying structure, we show how the different subparts of a fronto-parietal network are modulated by the semantic domain, over which the mathematical formulae are interpreted. Within this network, the prefrontal cortex represents a system that hosts three major components, namely, control, arithmetic-logic, and short-term memory. This prefrontal system operates on data fed to it by two other systems: a premotor-parietal top-down system that updates and transforms (external) data into an internal format, and a hippocampal bottom-up system that either detects novel information or serves as an access device to memory for previously acquired knowledge.

Usage of semantic representations in recognition memory.

PubMed

Nishiyama, Ryoji; Hirano, Tetsuji; Ukita, Jun

2017-11-01

Meanings of words facilitate false acceptance as well as correct rejection of lures in recognition memory tests, depending on the experimental context. This suggests that semantic representations are both directly and indirectly (i.e., mediated by perceptual representations) used in remembering. Studies using memory conjunction errors (MCEs) paradigms, in which the lures consist of component parts of studied words, have reported semantic facilitation of rejection of the lures. However, attending to components of the lures could potentially cause this. Therefore, we investigated whether semantic overlap of lures facilitates MCEs using Japanese Kanji words in which a whole-word image is more concerned in reading. Experiments demonstrated semantic facilitation of MCEs in a delayed recognition test (Experiment 1), and in immediate recognition tests in which participants were prevented from using phonological or orthographic representations (Experiment 2), and the salient effect on individuals with high semantic memory capacities (Experiment 3). Additionally, analysis of the receiver operating characteristic suggested that this effect is attributed to familiarity-based memory judgement and phantom recollection. These findings indicate that semantic representations can be directly used in remembering, even when perceptual representations of studied words are available.

Episodic and Semantic Memory Influences on Picture Naming in Alzheimer's Disease

ERIC Educational Resources Information Center

Small, Jeff A.; Sandhu, Nirmaljeet

2008-01-01

This study investigated the relationship between semantic and episodic memory as they support lexical access by healthy younger and older adults and individuals with Alzheimer's disease (AD). In particular, we were interested in examining the pattern of semantic and episodic memory declines in AD (i.e., word-finding difficulty and impaired recent…

Picture Superiority in Free Recall: The Effects of Organization and Elaboration.

ERIC Educational Resources Information Center

Ritchey, Gary H.

1980-01-01

Tests the notion that activation in children's semantic memory might best be considered in terms of both between-item and within-item elaboration. Subjects were 192 second, fourth, and sixth graders. (MP)

Audiovisual semantic congruency during encoding enhances memory performance.

PubMed

Heikkilä, Jenni; Alho, Kimmo; Hyvönen, Heidi; Tiippana, Kaisa

2015-01-01

Studies of memory and learning have usually focused on a single sensory modality, although human perception is multisensory in nature. In the present study, we investigated the effects of audiovisual encoding on later unisensory recognition memory performance. The participants were to memorize auditory or visual stimuli (sounds, pictures, spoken words, or written words), each of which co-occurred with either a semantically congruent stimulus, incongruent stimulus, or a neutral (non-semantic noise) stimulus in the other modality during encoding. Subsequent memory performance was overall better when the stimulus to be memorized was initially accompanied by a semantically congruent stimulus in the other modality than when it was accompanied by a neutral stimulus. These results suggest that semantically congruent multisensory experiences enhance encoding of both nonverbal and verbal materials, resulting in an improvement in their later recognition memory.

Unaware Memory in Hypothesis Generation Tasks

DTIC Science & Technology

1986-12-01

have been offered within the context of Tulving’s (1972) distinction between episodic and semantic memory systems (e.g., see Jacoby & - Witherspoon...in this direction (see Tulving, 1985) raise the possibility that neither episodic nor semantic memory systems can account for the type of unaware...material: Interactions with " episodic " and " semantic " memory . Conitive Psycholozv, 12, 227-251. Kolers, P. A. (1976). Reading a year later. Journal o

Graph-Theoretic Properties of Networks Based on Word Association Norms: Implications for Models of Lexical Semantic Memory

ERIC Educational Resources Information Center

Gruenenfelder, Thomas M.; Recchia, Gabriel; Rubin, Tim; Jones, Michael N.

2016-01-01

We compared the ability of three different contextual models of lexical semantic memory (BEAGLE, Latent Semantic Analysis, and the Topic model) and of a simple associative model (POC) to predict the properties of semantic networks derived from word association norms. None of the semantic models were able to accurately predict all of the network…

5W1H Information Extraction with CNN-Bidirectional LSTM

NASA Astrophysics Data System (ADS)

Nurdin, A.; Maulidevi, N. U.

2018-03-01

In this work, information about who, did what, when, where, why, and how on Indonesian news articles were extracted by combining Convolutional Neural Network and Bidirectional Long Short-Term Memory. Convolutional Neural Network can learn semantically meaningful representations of sentences. Bidirectional LSTM can analyze the relations among words in the sequence. We also use word embedding word2vec for word representation. By combining these algorithms, we obtained F-measure 0.808. Our experiments show that CNN-BLSTM outperforms other shallow methods, namely IBk, C4.5, and Naïve Bayes with the F-measure 0.655, 0.645, and 0.595, respectively.

Remote semantic memory is impoverished in hippocampal amnesia

PubMed Central

Klooster, Nathaniel B.; Duff, Melissa C.

2015-01-01

The necessity of the hippocampus for acquiring new semantic concepts is a topic of considerable debate. However, it is generally accepted that any role the hippocampus plays in semantic memory is time limited and that previously acquired information becomes independent of the hippocampus over time. This view, along with intact naming and word-definition matching performance in amnesia, has led to the notion that remote semantic memory is intact in patients with hippocampal amnesia. Motivated by perspectives of word learning as a protracted process where additional features and senses of a word are added over time, and by recent discoveries about the time course of hippocampal contributions to on-line relational processing, reconsolidation, and the flexible integration of information, we revisit the notion that remote semantic memory is intact in amnesia. Using measures of semantic richness and vocabulary depth from psycholinguistics and first and second language-learning studies, we examined how much information is associated with previously acquired, highly familiar words in a group of patients with bilateral hippocampal damage and amnesia. Relative to healthy demographically matched comparison participants and a group of brain-damaged comparison participants, the patients with hippocampal amnesia performed significantly worse on both productive and receptive measures of vocabulary depth and semantic richness. These findings suggest that remote semantic memory is impoverished in patients with hippocampal amnesia and that the hippocampus may play a role in the maintenance and updating of semantic memory beyond its initial acquisition. PMID:26474741

Semantic similarity between old and new items produces false alarms in recognition memory.

PubMed

Montefinese, Maria; Zannino, Gian Daniele; Ambrosini, Ettore

2015-09-01

In everyday life, human beings can report memories of past events that did not occur or that occurred differently from the way they remember them because memory is an imperfect process of reconstruction and is prone to distortion and errors. In this recognition study using word stimuli, we investigated whether a specific operationalization of semantic similarity among concepts can modulate false memories while controlling for the possible effect of associative strength and word co-occurrence in an old-new recognition task. The semantic similarity value of each new concept was calculated as the mean cosine similarity between pairs of vectors representing that new concept and each old concept belonging to the same semantic category. Results showed that, compared with (new) low-similarity concepts, (new) high-similarity concepts had significantly higher probability of being falsely recognized as old, even after partialling out the effect of confounding variables, including associative relatedness and lexical co-occurrence. This finding supports the feature-based view of semantic memory, suggesting that meaning overlap and sharing of semantic features (which are greater when more similar semantic concepts are being processed) have an influence on recognition performance, resulting in more false alarms for new high-similarity concepts. We propose that the associative strength and word co-occurrence among concepts are not sufficient to explain illusory memories but is important to take into account also the effects of feature-based semantic relations, and, in particular, the semantic similarity among concepts.

Remote semantic memory is impoverished in hippocampal amnesia.

PubMed

Klooster, Nathaniel B; Duff, Melissa C

2015-12-01

The necessity of the hippocampus for acquiring new semantic concepts is a topic of considerable debate. However, it is generally accepted that any role the hippocampus plays in semantic memory is time limited and that previously acquired information becomes independent of the hippocampus over time. This view, along with intact naming and word-definition matching performance in amnesia, has led to the notion that remote semantic memory is intact in patients with hippocampal amnesia. Motivated by perspectives of word learning as a protracted process where additional features and senses of a word are added over time, and by recent discoveries about the time course of hippocampal contributions to on-line relational processing, reconsolidation, and the flexible integration of information, we revisit the notion that remote semantic memory is intact in amnesia. Using measures of semantic richness and vocabulary depth from psycholinguistics and first and second language-learning studies, we examined how much information is associated with previously acquired, highly familiar words in a group of patients with bilateral hippocampal damage and amnesia. Relative to healthy demographically matched comparison participants and a group of brain-damaged comparison participants, the patients with hippocampal amnesia performed significantly worse on both productive and receptive measures of vocabulary depth and semantic richness. These findings suggest that remote semantic memory is impoverished in patients with hippocampal amnesia and that the hippocampus may play a role in the maintenance and updating of semantic memory beyond its initial acquisition. Copyright © 2015 Elsevier Ltd. All rights reserved.

Retrieval from Memory: Vulnerable or Inviolable?

ERIC Educational Resources Information Center

Jones, Dylan M.; Marsh, John E.; Hughes, Robert W.

2012-01-01

We show that retrieval from semantic memory is vulnerable even to the mere presence of speech. Irrelevant speech impairs semantic fluency--namely, lexical retrieval cued by a semantic category name--but only if it is meaningful (forward speech compared to reversed speech or words compared to nonwords). Moreover, speech related semantically to the…

Memory color effect induced by familiarity of brand logos.

PubMed

Kimura, Atsushi; Wada, Yuji; Masuda, Tomohiro; Goto, Sho-Ichi; Tsuzuki, Daisuke; Hibino, Haruo; Cai, Dongsheng; Dan, Ippeita

2013-01-01

When people are asked to adjust the color of familiar objects such as fruits until they appear achromatic, the subjective gray points of the objects are shifted away from the physical gray points in a direction opposite to the memory color (memory color effect). It is still unclear whether the discrepancy between memorized and actual colors of objects is dependent on the familiarity of the objects. Here, we conducted two experiments in order to examine the relationship between the degree of a subject's familiarity with objects and the degree of the memory color effect by using logographs of food and beverage companies. In Experiment 1, we measured the memory color effects of logos which varied in terms of their familiarity (high, middle, or low). Results demonstrate that the memory color effect occurs only in the high-familiarity condition, but not in the middle- and low-familiarity conditions. Furthermore, there is a positive correlation between the memory color effect and the actual number of domestic stores of the brand. In Experiment 2, we assessed the semantic association between logos and food/beverage names by using a semantic priming task to elucidate whether the memory color effect of logos relates to consumer brand cognition, and found that the semantic associations between logos and food/beverage names in the high-familiarity brands were stronger than those in the low-familiarity brands only when the logos were colored correctly, but not when they were appropriately or inappropriately colored, or achromatic. The current results provide behavioral evidence of the relationship between the familiarity of objects and the memory color effect and suggest that the memory color effect increases with the familiarity of objects, albeit not constantly.

Memory Color Effect Induced by Familiarity of Brand Logos

PubMed Central

Kimura, Atsushi; Wada, Yuji; Masuda, Tomohiro; Goto, Sho-ichi; Tsuzuki, Daisuke; Hibino, Haruo; Cai, Dongsheng; Dan, Ippeita

2013-01-01

Background When people are asked to adjust the color of familiar objects such as fruits until they appear achromatic, the subjective gray points of the objects are shifted away from the physical gray points in a direction opposite to the memory color (memory color effect). It is still unclear whether the discrepancy between memorized and actual colors of objects is dependent on the familiarity of the objects. Here, we conducted two experiments in order to examine the relationship between the degree of a subject’s familiarity with objects and the degree of the memory color effect by using logographs of food and beverage companies. Methods and Findings In Experiment 1, we measured the memory color effects of logos which varied in terms of their familiarity (high, middle, or low). Results demonstrate that the memory color effect occurs only in the high-familiarity condition, but not in the middle- and low-familiarity conditions. Furthermore, there is a positive correlation between the memory color effect and the actual number of domestic stores of the brand. In Experiment 2, we assessed the semantic association between logos and food/beverage names by using a semantic priming task to elucidate whether the memory color effect of logos relates to consumer brand cognition, and found that the semantic associations between logos and food/beverage names in the high-familiarity brands were stronger than those in the low-familiarity brands only when the logos were colored correctly, but not when they were appropriately or inappropriately colored, or achromatic. Conclusion The current results provide behavioral evidence of the relationship between the familiarity of objects and the memory color effect and suggest that the memory color effect increases with the familiarity of objects, albeit not constantly. PMID:23874638

How do episodic and semantic memory contribute to episodic foresight in young children?

PubMed

Martin-Ordas, Gema; Atance, Cristina M; Caza, Julian S

2014-01-01

Humans are able to transcend the present and mentally travel to another time, place, or perspective. Mentally projecting ourselves backwards (i.e., episodic memory) or forwards (i.e., episodic foresight) in time are crucial characteristics of the human memory system. Indeed, over the past few years, episodic memory has been argued to be involved both in our capacity to retrieve our personal past experiences and in our ability to imagine and foresee future scenarios. However, recent theory and findings suggest that semantic memory also plays a significant role in imagining future scenarios. We draw on Tulving's definition of episodic and semantic memory to provide a critical analysis of their role in episodic foresight tasks described in the developmental literature. We conclude by suggesting future directions of research that could further our understanding of how both episodic memory and semantic memory are intimately connected to episodic foresight.

How do episodic and semantic memory contribute to episodic foresight in young children?

PubMed Central

Martin-Ordas, Gema; Atance, Cristina M.; Caza, Julian S.

2014-01-01

Humans are able to transcend the present and mentally travel to another time, place, or perspective. Mentally projecting ourselves backwards (i.e., episodic memory) or forwards (i.e., episodic foresight) in time are crucial characteristics of the human memory system. Indeed, over the past few years, episodic memory has been argued to be involved both in our capacity to retrieve our personal past experiences and in our ability to imagine and foresee future scenarios. However, recent theory and findings suggest that semantic memory also plays a significant role in imagining future scenarios. We draw on Tulving’s definition of episodic and semantic memory to provide a critical analysis of their role in episodic foresight tasks described in the developmental literature. We conclude by suggesting future directions of research that could further our understanding of how both episodic memory and semantic memory are intimately connected to episodic foresight. PMID:25071690

Working memory and semantic involvement in sentence processing: a case of pure progressive amnesia.

PubMed

Fossard, Marion; Rigalleau, François; Puel, Michèle; Nespoulous, Jean-Luc; Viallard, Gérard; Démonet, Jean-François; Cardebat, Dominique

2006-01-01

ED, a 83-year-old woman, meets the criteria of pure progressive amnesia, with gradual impairment of episodic and autobiographical memory, sparing of semantic processing and strong working memory (WM) deficit. The dissociation between disturbed WM and spared semantic processing permitted testing the role of WM in processing anaphors like pronouns or repeated names. Results showed a globally normal anaphoric behavior in two experiments requiring anaphoric processing in sentence production and comprehension. We suggest that preserved semantic processing in ED would have compensated for working memory deficit in anaphoric processing.

Randomized controlled trial evaluating the temporal effects of high-intensity exercise on learning, short-term and long-term memory, and prospective memory.

PubMed

Frith, Emily; Sng, Eveleen; Loprinzi, Paul D

2017-11-01

The broader purpose of this study was to examine the temporal effects of high-intensity exercise on learning, short-term and long-term retrospective memory and prospective memory. Among a sample of 88 young adult participants, 22 were randomized into one of four different groups: exercise before learning, control group, exercise during learning, and exercise after learning. The retrospective assessments (learning, short-term and long-term memory) were assessed using the Rey Auditory Verbal Learning Test. Long-term memory including a 20-min and 24-hr follow-up assessment. Prospective memory was assessed using a time-based procedure by having participants contact (via phone) the researchers at a follow-up time period. The exercise stimulus included a 15-min bout of progressive maximal exertion treadmill exercise. High-intensity exercise prior to memory encoding (vs. exercise during memory encoding or consolidation) was effective in enhancing long-term memory (for both 20-min and 24-h follow-up assessments). We did not observe a differential temporal effect of high-intensity exercise on short-term memory (immediate post-memory encoding), learning or prospective memory. The timing of high-intensity exercise may play an important role in facilitating long-term memory. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Age Invariance in Semantic and Episodic Metamemory: Both Younger and Older Adults Provide Accurate Feeling of Knowing For Names of Faces

PubMed Central

Eakin, Deborah K.; Hertzog, Christopher; Harris, William

2013-01-01

Age differences in feeling-of-knowing (FOK) accuracy were examined for both episodic memory and semantic memory. Younger and older adults either viewed pictures of famous faces (semantic memory) or associated nonfamous faces and names (episodic memory) and were tested on their memory for the name of the presented face. Participants viewed the faces again and made a FOK prediction about future recognition of the name associated with the presented face. Finally, four-alternative forced-choice recognition memory for the name, cued by the face, was tested and confidence judgments (CJs) were collected for each recognition response. Age differences were not obtained in semantic memory or the resolution of semantic FOKs, defined by within-person correlations of FOKs with recognition memory performance. Although age differences were obtained in level of episodic memory, there were no age differences in the resolution of episodic FOKs. FOKs for correctly recognized items correlated reliably with CJs for both types of materials, and did not differ by age group. The results indicate age invariance in monitoring of retrieval processes for name-face associations. PMID:23537379

Age invariance in semantic and episodic metamemory: both younger and older adults provide accurate feeling-of-knowing for names of faces.

PubMed

Eakin, Deborah K; Hertzog, Christopher; Harris, William

2014-01-01

Age differences in feeling-of-knowing (FOK) accuracy were examined for both episodic memory and semantic memory. Younger and older adults either viewed pictures of famous faces (semantic memory) or associated non-famous faces and names (episodic memory) and were tested on their memory for the name of the presented face. Participants viewed the faces again and made a FOK prediction about future recognition of the name associated with the presented face. Finally, four-alternative forced-choice recognition memory for the name, cued by the face, was tested and confidence judgments (CJs) were collected for each recognition response. Age differences were not obtained in semantic memory or the resolution of semantic FOKs, defined by within-person correlations of FOKs with recognition memory performance. Although age differences were obtained in level of episodic memory, there were no age differences in the resolution of episodic FOKs. FOKs for correctly recognized items correlated reliably with CJs for both types of materials, and did not differ by age group. The results indicate age invariance in monitoring of retrieval processes for name-face associations.

The association of personal semantic memory to identity representations: insight into higher-order networks of autobiographical contents.

PubMed

Grilli, Matthew D

2017-11-01

Identity representations are higher-order knowledge structures that organise autobiographical memories on the basis of personality and role-based themes of one's self-concept. In two experiments, the extent to which different types of personal semantic content are reflected in these higher-order networks of memories was investigated. Healthy, young adult participants generated identity representations that varied in remoteness of formation and verbally reflected on these themes in an open-ended narrative task. The narrative responses were scored for retrieval of episodic, experience-near personal semantic and experience-far (i.e., abstract) personal semantic contents. Results revealed that to reflect on remotely formed identity representations, experience-far personal semantic contents were retrieved more than experience-near personal semantic contents. In contrast, to reflect on recently formed identity representations, experience-near personal semantic contents were retrieved more than experience-far personal semantic contents. Although episodic memory contents were retrieved less than both personal semantic content types to reflect on remotely formed identity representations, this content type was retrieved at a similar frequency as experience-far personal semantic content to reflect on recently formed identity representations. These findings indicate that the association of personal semantic content to identity representations is robust and related to time since acquisition of these knowledge structures.

No one way ticket from orthography to semantics in recognition memory: N400 and P200 effects of associations.

PubMed

Stuellein, Nicole; Radach, Ralph R; Jacobs, Arthur M; Hofmann, Markus J

2016-05-15

Computational models of word recognition already successfully used associative spreading from orthographic to semantic levels to account for false memories. But can they also account for semantic effects on event-related potentials in a recognition memory task? To address this question, target words in the present study had either many or few semantic associates in the stimulus set. We found larger P200 amplitudes and smaller N400 amplitudes for old words in comparison to new words. Words with many semantic associates led to larger P200 amplitudes and a smaller N400 in comparison to words with a smaller number of semantic associations. We also obtained inverted response time and accuracy effects for old and new words: faster response times and fewer errors were found for old words that had many semantic associates, whereas new words with a large number of semantic associates produced slower response times and more errors. Both behavioral and electrophysiological results indicate that semantic associations between words can facilitate top-down driven lexical access and semantic integration in recognition memory. Our results support neurophysiologically plausible predictions of the Associative Read-Out Model, which suggests top-down connections from semantic to orthographic layers. Copyright © 2016 Elsevier B.V. All rights reserved.

PKA increases in the olfactory bulb act as unconditioned stimuli and provide evidence for parallel memory systems: pairing odor with increased PKA creates intermediate- and long-term, but not short-term, memories.

PubMed

Grimes, Matthew T; Harley, Carolyn W; Darby-King, Andrea; McLean, John H

2012-02-21

Neonatal odor-preference memory in rat pups is a well-defined associative mammalian memory model dependent on cAMP. Previous work from this laboratory demonstrates three phases of neonatal odor-preference memory: short-term (translation-independent), intermediate-term (translation-dependent), and long-term (transcription- and translation-dependent). Here, we use neonatal odor-preference learning to explore the role of olfactory bulb PKA in these three phases of mammalian memory. PKA activity increased normally in learning animals 10 min after a single training trial. Inhibition of PKA by Rp-cAMPs blocked intermediate-term and long-term memory, with no effect on short-term memory. PKA inhibition also prevented learning-associated CREB phosphorylation, a transcription factor implicated in long-term memory. When long-term memory was rescued through increased β-adrenoceptor activation, CREB phosphorylation was restored. Intermediate-term and long-term, but not short-term odor-preference memories were generated by pairing odor with direct PKA activation using intrabulbar Sp-cAMPs, which bypasses β-adrenoceptor activation. Higher levels of Sp-cAMPs enhanced memory by extending normal 24-h retention to 48-72 h. These results suggest that increased bulbar PKA is necessary and sufficient for the induction of intermediate-term and long-term odor-preference memory, and suggest that PKA activation levels also modulate memory duration. However, short-term memory appears to use molecular mechanisms other than the PKA/CREB pathway. These mechanisms, which are also recruited by β-adrenoceptor activation, must operate in parallel with PKA activation.

The Episodic/Semantic Memory Distinction as an Heuristic in the Study of Instructional Effects on Cognitive Structure.

ERIC Educational Resources Information Center

Konold, Clifford E.; Bates, John A.

1982-01-01

Significant correlations between measures of cognitive structure and performance were found using a procedure distinguishing between episodic and semantic memory as an heuristic with achievement test items. The design increased the likelihood of indications of semantic memory. Higher-order and lower-order cognitive processes are discussed.…

Medical Concept Normalization in Social Media Posts with Recurrent Neural Networks.

PubMed

Tutubalina, Elena; Miftahutdinov, Zulfat; Nikolenko, Sergey; Malykh, Valentin

2018-06-12

Text mining of scientific libraries and social media has already proven itself as a reliable tool for drug repurposing and hypothesis generation. The task of mapping a disease mention to a concept in a controlled vocabulary, typically to the standard thesaurus in the Unified Medical Language System (UMLS), is known as medical concept normalization. This task is challenging due to the differences in the use of medical terminology between health care professionals and social media texts coming from the lay public. To bridge this gap, we use sequence learning with recurrent neural networks and semantic representation of one- or multi-word expressions: we develop end-to-end architectures directly tailored to the task, including bidirectional Long Short-Term Memory, Gated Recurrent Units with an attention mechanism, and additional semantic similarity features based on UMLS. Our evaluation against a standard benchmark shows that recurrent neural networks improve results over an effective baseline for classification based on convolutional neural networks. A qualitative examination of mentions discovered in a dataset of user reviews collected from popular online health information platforms as well as a quantitative evaluation both show improvements in the semantic representation of health-related expressions in social media. Copyright © 2018. Published by Elsevier Inc.

Depletion of Serotonin Selectively Impairs Short-Term Memory without Affecting Long-Term Memory in Odor Learning in the Terrestrial Slug "Limax Valentianus"

ERIC Educational Resources Information Center

Santa, Tomofumi; Kirino, Yutaka; Watanabe, Satoshi; Shirahata, Takaaki; Tsunoda, Makoto

2006-01-01

The terrestrial slug "Limax" is able to acquire short-term and long-term memories during aversive odor-taste associative learning. We investigated the effect of the selective serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) on memory. Behavioral studies indicated that 5,7-DHT impaired short-term memory but not long-term memory. HPLC…

Semantic memory and frontal executive function during transient global amnesia.

PubMed

Hodges, J R

1994-05-01

To assess semantic memory and frontal executive function, two patients underwent neuropsychological testing during transient global amnesia (TGA) and after an interval of 6-8 weeks. In spite of a profound deficit in anterograde verbal and non-verbal memory, semantic memory was normal, as judged by category fluency measures, picture naming, and picture-word and picture-picture matching, and reading ability was normal. Similarly, there were no deficits on a number of tests known to be sensitive to frontal executive dysfunction. A hexamethylpropyleneamine-oxime (HMPAO) single photon emission CT (SPECT) scan, obtained on one patient 24 hours post-TGA, showed focal left temporal lobe hypoperfusion which had resolved three months later. The observed dissociation between episodic and semantic memory is discussed in the light of contemporary cognitive theories of memory organisation.

The Histone Deacetylase HDAC4 Regulates Long-Term Memory in Drosophila

PubMed Central

Fitzsimons, Helen L.; Schwartz, Silvia; Given, Fiona M.; Scott, Maxwell J.

2013-01-01

A growing body of research indicates that pharmacological inhibition of histone deacetylases (HDACs) correlates with enhancement of long-term memory and current research is concentrated on determining the roles that individual HDACs play in cognitive function. Here, we investigate the role of HDAC4 in long-term memory formation in Drosophila. We show that overexpression of HDAC4 in the adult mushroom body, an important structure for memory formation, resulted in a specific impairment in long-term courtship memory, but had no affect on short-term memory. Overexpression of an HDAC4 catalytic mutant also abolished LTM, suggesting a mode of action independent of catalytic activity. We found that overexpression of HDAC4 resulted in a redistribution of the transcription factor MEF2 from a relatively uniform distribution through the nucleus into punctate nuclear bodies, where it colocalized with HDAC4. As MEF2 has also been implicated in regulation of long-term memory, these data suggest that the repressive effects of HDAC4 on long-term memory may be through interaction with MEF2. In the same genetic background, we also found that RNAi-mediated knockdown of HDAC4 impairs long-term memory, therefore we demonstrate that HDAC4 is not only a repressor of long-term memory, but also modulates normal memory formation. PMID:24349558

The Interaction between Semantic Representation and Episodic Memory.

PubMed

Fang, Jing; Rüther, Naima; Bellebaum, Christian; Wiskott, Laurenz; Cheng, Sen

2018-02-01

The experimental evidence on the interrelation between episodic memory and semantic memory is inconclusive. Are they independent systems, different aspects of a single system, or separate but strongly interacting systems? Here, we propose a computational role for the interaction between the semantic and episodic systems that might help resolve this debate. We hypothesize that episodic memories are represented as sequences of activation patterns. These patterns are the output of a semantic representational network that compresses the high-dimensional sensory input. We show quantitatively that the accuracy of episodic memory crucially depends on the quality of the semantic representation. We compare two types of semantic representations: appropriate representations, which means that the representation is used to store input sequences that are of the same type as those that it was trained on, and inappropriate representations, which means that stored inputs differ from the training data. Retrieval accuracy is higher for appropriate representations because the encoded sequences are less divergent than those encoded with inappropriate representations. Consistent with our model prediction, we found that human subjects remember some aspects of episodes significantly more accurately if they had previously been familiarized with the objects occurring in the episode, as compared to episodes involving unfamiliar objects. We thus conclude that the interaction with the semantic system plays an important role for episodic memory.

Retrograde Amnesia for Episodic and Semantic Memories in Amnestic Mild Cognitive Impairment.

PubMed

De Simone, Maria Stefania; Fadda, Lucia; Perri, Roberta; De Tollis, Massimo; Aloisi, Marta; Caltagirone, Carlo; Carlesimo, Giovanni Augusto

2017-01-01

Retrograde amnesia (RA), which includes loss of memory for past personal events (autobiographical RA) and for acquired knowledge (semantic RA), has been largely documented in patients with amnestic mild cognitive impairment (aMCI). However, previous studies have produced controversial results particularly concerning the temporal extent of memory impairment. Here we investigated whether, with the onset of hippocampal pathology, age of memory acquisition and retrieval frequency play different roles in modulating the progressive loss of semantic and episodic contents of retrograde memory respectively. For this purpose, aMCI patients and healthy controls were tested for the ability to recall semantic and autobiographical information related to famous public events as a function of both age of acquisition and retrieval frequency. In aMCI patients, we found that the impairment in recollecting past personal incidents was modulated by the combined action of memory age and retrieval frequency, because older and more frequently retrieved episodes are less susceptible to loss than more recent and less frequently retrieved ones. On the other side, we found that the loss of semantic information depended only on memory age, because the remoteness of the trace allows for better preservation of the memory. Our results provide evidence that the loss of the two components of retrograde memory is regulated by different mechanisms. This supports the view that diverse neural mechanisms are involved in episodic and semantic memory trace storage and retrieval, as postulated by the Multiple Trace Theory.

Analysis of acute naproxen administration on memory in young adults: A randomized, double-blind, placebo-controlled study.

PubMed

Wilson, Jack H; Criss, Amy H; Spangler, Sean A; Walukevich, Katherine; Hewett, Sandra

2017-10-01

Nonsteroidal anti-inflammatory drugs work by non-selectively inhibiting cyclooxygenase enzymes. Evidence indicates that metabolites of the cyclooxygenase pathway play a critical role in the process of learning and memory. We evaluated whether acute naproxen treatment impairs short-term working memory, episodic memory, or semantic memory in a young, healthy adult population. Participants received a single dose of placebo or naproxen (750 mg) in random order separated by 7-10 days. Two hours following administration, participants completed five memory tasks. The administration of acute high-dose naproxen had no effect on memory in healthy young adults.

The Metamemory Approach to Confidence: A Test Using Semantic Memory

ERIC Educational Resources Information Center

Brewer, William F.; Sampaio, Cristina

2012-01-01

The metamemory approach to memory confidence was extended and elaborated to deal with semantic memory tasks. The metamemory approach assumes that memory confidence is based on the products and processes of a completed memory task, as well as metamemory beliefs that individuals have about how their memory products and processes relate to memory…

Concealed semantic and episodic autobiographical memory electrified.

PubMed

Ganis, Giorgio; Schendan, Haline E

2012-01-01

Electrophysiology-based concealed information tests (CIT) try to determine whether somebody possesses concealed information about a crime-related item (probe) by comparing event-related potentials (ERPs) between this item and comparison items (irrelevants). Although the broader field is sometimes referred to as "memory detection," little attention has been paid to the precise type of underlying memory involved. This study begins addressing this issue by examining the key distinction between semantic and episodic memory in the autobiographical domain within a CIT paradigm. This study also addresses the issue of whether multiple repetitions of the items over the course of the session habituate the brain responses. Participants were tested in a 3-stimulus CIT with semantic autobiographical probes (their own date of birth) and episodic autobiographical probes (a secret date learned just before the study). Results dissociated these two memory conditions on several ERP components. Semantic probes elicited a smaller frontal N2 than episodic probes, consistent with the idea that the frontal N2 decreases with greater pre-existing knowledge about the item. Likewise, semantic probes elicited a smaller central N400 than episodic probes. Semantic probes also elicited a larger P3b than episodic probes because of their richer meaning. In contrast, episodic probes elicited a larger late positive complex (LPC) than semantic probes, because of the recent episodic memory associated with them. All these ERPs showed a difference between probes and irrelevants in both memory conditions, except for the N400, which showed a difference only in the semantic condition. Finally, although repetition affected the ERPs, it did not reduce the difference between probes and irrelevants. These findings show that the type of memory associated with a probe has both theoretical and practical importance for CIT research.

Concealed semantic and episodic autobiographical memory electrified

PubMed Central

Ganis, Giorgio; Schendan, Haline E.

2013-01-01

Electrophysiology-based concealed information tests (CIT) try to determine whether somebody possesses concealed information about a crime-related item (probe) by comparing event-related potentials (ERPs) between this item and comparison items (irrelevants). Although the broader field is sometimes referred to as “memory detection,” little attention has been paid to the precise type of underlying memory involved. This study begins addressing this issue by examining the key distinction between semantic and episodic memory in the autobiographical domain within a CIT paradigm. This study also addresses the issue of whether multiple repetitions of the items over the course of the session habituate the brain responses. Participants were tested in a 3-stimulus CIT with semantic autobiographical probes (their own date of birth) and episodic autobiographical probes (a secret date learned just before the study). Results dissociated these two memory conditions on several ERP components. Semantic probes elicited a smaller frontal N2 than episodic probes, consistent with the idea that the frontal N2 decreases with greater pre-existing knowledge about the item. Likewise, semantic probes elicited a smaller central N400 than episodic probes. Semantic probes also elicited a larger P3b than episodic probes because of their richer meaning. In contrast, episodic probes elicited a larger late positive complex (LPC) than semantic probes, because of the recent episodic memory associated with them. All these ERPs showed a difference between probes and irrelevants in both memory conditions, except for the N400, which showed a difference only in the semantic condition. Finally, although repetition affected the ERPs, it did not reduce the difference between probes and irrelevants. These findings show that the type of memory associated with a probe has both theoretical and practical importance for CIT research. PMID:23355816

The Korsakoff syndrome: clinical aspects, psychology and treatment.

PubMed

Kopelman, Michael D; Thomson, Allan D; Guerrini, Irene; Marshall, E Jane

2009-01-01

The Korsakoff syndrome is a preventable memory disorder that usually emerges (although not always) in the aftermath of an episode of Wernicke's encephalopathy. The present paper reviews the clinical and scientific literature on this disorder. A systematic review of the clinical and scientific literature on Wernicke's encephalopathy and the alcoholic Korsakoff syndrome. The Korsakoff syndrome is most commonly associated with chronic alcohol misuse, and some heavy drinkers may have a genetic predisposition to developing the syndrome. The characteristic neuropathology includes neuronal loss, micro-haemorrhages and gliosis in the paraventricular and peri-aqueductal grey matter. Lesions in the mammillary bodies, the mammillo-thalamic tract and the anterior thalamus may be more important to memory dysfunction than lesions in the medial dorsal nucleus of the thalamus. Episodic memory is severely affected in the Korsakoff syndrome, and the learning of new semantic memories is variably affected. 'Implicit' aspects of memory are preserved. These patients are often first encountered in general hospital settings where they can occupy acute medical beds for lengthy periods. Abstinence is the cornerstone of any rehabilitation programme. Korsakoff patients are capable of new learning, particularly if they live in a calm and well-structured environment and if new information is cued. There are few long-term follow-up studies, but these patients are reported to have a normal life expectancy if they remain abstinent from alcohol. Although we now have substantial knowledge about the nature of this disorder, scientific questions (e.g. regarding the underlying genetics) remain. More particularly, there is a dearth of appropriate long-term care facilities for these patients, given that empirical research has shown that good practice has beneficial effects.

Distinct regions of prefrontal cortex are associated with the controlled retrieval and selection of social information.

PubMed

Satpute, Ajay B; Badre, David; Ochsner, Kevin N

2014-05-01

Research in social neuroscience has uncovered a social knowledge network that is particularly attuned to making social judgments. However, the processes that are being performed by both regions within this network and those outside of this network that are nevertheless engaged in the service of making a social judgment remain unclear. To help address this, we drew upon research in semantic memory, which suggests that making a semantic judgment engages 2 distinct control processes: A controlled retrieval process, which aids in bringing goal-relevant information to mind from long-term stores, and a selection process, which aids in selecting the information that is goal-relevant from the information retrieved. In a neuroimaging study, we investigated whether controlled retrieval and selection for social information engage distinct portions of both the social knowledge network and regions outside this network. Controlled retrieval for social information engaged an anterior ventrolateral portion of the prefrontal cortex, whereas selection engaged both the dorsomedial prefrontal cortex and temporoparietal junction within the social knowledge network. These results suggest that the social knowledge network may be more involved with the selection of social information than the controlled retrieval of it and incorporates lateral prefrontal regions in accessing memory for making social judgments.

Amnesia in an actor: Learning and re-learning of play passages despite severe autobiographical amnesia.

PubMed

Kopelman, Michael D; Morton, John

2015-06-01

We describe the case of an accomplished actor, whom we term AB, who suffered severe amnesia following a cardiac arrest and hypoxic brain damage, affecting medial temporal and thalamic structures. His performance on standard episodic memory tests, and on measures of retrograde amnesia, including autobiographical memory, was severely impaired. When presented with passages from plays he had not appeared in, AB showed a severe impairment at the first learning trial, but thereafter showed a 'normal' learning curve for this semantically and syntactically complex material. On being presented with passages from plays he had performed in the past, AB did not show any recognition of them whatsoever, as one might expect from his severe episodic memory impairment. However, AB showed a striking benefit (savings score) in relearning passages he had previously performed, compared with new passages, despite not having any autobiographical recall of having performed the relearned passages before. Moreover, although his initial recall performance in learning these passages was impaired compared with healthy control actors of similar age and experience, AB demonstrated the same incremental learning rate on subsequent learning trials of the passages as did the controls. We conclude that, although severely impaired at the first learning trial (on both 'new' and 'old' passages), AB was able to employ his long-established semantic and procedural skills to attempt the task, and that thereafter he showed a 'normal' rate of incremental learning from a lower baseline. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Semantic memory: a feature-based analysis and new norms for Italian.

PubMed

Montefinese, Maria; Ambrosini, Ettore; Fairfield, Beth; Mammarella, Nicola

2013-06-01

Semantic norms for properties produced by native speakers are valuable tools for researchers interested in the structure of semantic memory and in category-specific semantic deficits in individuals following brain damage. The aims of this study were threefold. First, we sought to extend existing semantic norms by adopting an empirical approach to category (Exp. 1) and concept (Exp. 2) selection, in order to obtain a more representative set of semantic memory features. Second, we extensively outlined a new set of semantic production norms collected from Italian native speakers for 120 artifactual and natural basic-level concepts, using numerous measures and statistics following a feature-listing task (Exp. 3b). Finally, we aimed to create a new publicly accessible database, since only a few existing databases are publicly available online.

Looking for episodic memory in animals and young children: prospects for a new minimalism.

PubMed

Clayton, Nicola S; Russell, James

2009-09-01

Because animals and young children cannot be interrogated about their experiences it is difficult to conduct research into their episodic memories. The approach to this issue adopted by Clayton and Dickinson [Clayton, N. S., & Dickinson, A. (1998). Episodic-like memory during cache recovery by scrub jays. Nature, 395, 272-274] was to take a conceptually minimalist definition of episodic memory, in terms of integrating information about what was done where and when [Tulving, E. (1972). Episodic and semantic memory. In E. Tulving, & W. Donaldson (Eds.), Organisation of memory (pp. 381-403). New York: Academic Press], and to refer to such memories as 'episodic-like'. Some claim, however, that because animals supposedly lack the conceptual abilities necessary for episodic recall one should properly call these memories 'semantic'. We address this debate with a novel approach to episodic memory, which is minimalist insofar as it focuses on the non-conceptual content of a re-experienced situation. It rests on Kantian assumptions about the necessary 'perspectival' features of any objective experience or re-experience. We show how adopting this perspectival approach can render an episodic interpretation of the animal data more plausible and can also reveal patterns in the mosaic of developmental evidence for episodic memory in humans.

Short-term plasticity as a neural mechanism supporting memory and attentional functions.

PubMed

Jääskeläinen, Iiro P; Ahveninen, Jyrki; Andermann, Mark L; Belliveau, John W; Raij, Tommi; Sams, Mikko

2011-11-08

Based on behavioral studies, several relatively distinct perceptual and cognitive functions have been defined in cognitive psychology such as sensory memory, short-term memory, and selective attention. Here, we review evidence suggesting that some of these functions may be supported by shared underlying neuronal mechanisms. Specifically, we present, based on an integrative review of the literature, a hypothetical model wherein short-term plasticity, in the form of transient center-excitatory and surround-inhibitory modulations, constitutes a generic processing principle that supports sensory memory, short-term memory, involuntary attention, selective attention, and perceptual learning. In our model, the size and complexity of receptive fields/level of abstraction of neural representations, as well as the length of temporal receptive windows, increases as one steps up the cortical hierarchy. Consequently, the type of input (bottom-up vs. top down) and the level of cortical hierarchy that the inputs target, determine whether short-term plasticity supports purely sensory vs. semantic short-term memory or attentional functions. Furthermore, we suggest that rather than discrete memory systems, there are continuums of memory representations from short-lived sensory ones to more abstract longer-duration representations, such as those tapped by behavioral studies of short-term memory. Copyright © 2011 Elsevier B.V. All rights reserved.

Selective preservation of memory for people in the context of semantic memory disorder: patterns of association and dissociation.

PubMed

Lyons, Frances; Kay, Janice; Hanley, J Richard; Haslam, Catherine

2006-01-01

A number of single cases in the literature demonstrate that person-specific semantic knowledge can be selectively impaired after acquired brain damage compared with that of object categories. However, there has been little unequivocal evidence for the reverse dissociation, selective preservation of person-specific semantic knowledge. Recently, three case studies have been published which provide support for the claim that such knowledge can be selectively preserved [Kay, J., & Hanley, J. R. (2002). Preservation of memory for people in semantic memory disorder: Further category-specific semantic dissociation. Cognitive Neuropsychology, 19, 113-134; Lyons, F., Hanley, J. R., & Kay, J. (2002). Anomia for common names and geographical names with preserved retrieval of names of people: A semantic memory disorder. Cortex, 38, 23-35; Thompson, S. A, Graham, K. S., Williams, G., Patterson, K., Kapur, N., & Hodges, J. R. (2004). Dissociating person-specific from general semantic knowledge: Roles of the left and right temporal lobes. Neuropsychologia, 42, 359-370]. In this paper, we supply further evidence from a series of 18 patients with acquired language disorder. Of this set, a number were observed to be impaired on tests of semantic association and word-picture matching using names of object categories (e.g. objects, animals and foods), but preserved on similar tests using names of famous people. Careful methodology was applied to match object and person-specific categories for item difficulty. The study also examined whether preservation of person-specific semantic knowledge was associated with preservation of knowledge of 'biological categories' such as fruit and vegetables and animals, or with preservation of 'token' knowledge of singular categories such as countries. The findings are discussed in the context of a variety of accounts that examine whether semantic memory has a categorical structure.

Interpreting semantic clustering effects in free recall.

PubMed

Manning, Jeremy R; Kahana, Michael J

2012-07-01

The order in which participants choose to recall words from a studied list of randomly selected words provides insights into how memories of the words are represented, organised, and retrieved. One pervasive finding is that when a pair of semantically related words (e.g., "cat" and "dog") is embedded in the studied list, the related words are often recalled successively. This tendency to successively recall semantically related words is termed semantic clustering (Bousfield, 1953; Bousfield & Sedgewick, 1944; Cofer, Bruce, & Reicher, 1966). Measuring semantic clustering effects requires making assumptions about which words participants consider to be similar in meaning. However, it is often difficult to gain insights into individual participants' internal semantic models, and for this reason researchers typically rely on standardised semantic similarity metrics. Here we use simulations to gain insights into the expected magnitudes of semantic clustering effects given systematic differences between participants' internal similarity models and the similarity metric used to quantify the degree of semantic clustering. Our results provide a number of useful insights into the interpretation of semantic clustering effects in free recall.

How activation, entanglement, and searching a semantic network contribute to event memory.

PubMed

Nelson, Douglas L; Kitto, Kirsty; Galea, David; McEvoy, Cathy L; Bruza, Peter D

2013-08-01

Free-association norms indicate that words are organized into semantic/associative neighborhoods within a larger network of words and links that bind the net together. We present evidence indicating that memory for a recent word event can depend on implicitly and simultaneously activating related words in its neighborhood. Processing a word during encoding primes its network representation as a function of the density of the links in its neighborhood. Such priming increases recall and recognition and can have long-lasting effects when the word is processed in working memory. Evidence for this phenomenon is reviewed in extralist-cuing, primed free-association, intralist-cuing, and single-item recognition tasks. The findings also show that when a related word is presented in order to cue the recall of a studied word, the cue activates the target in an array of related words that distract and reduce the probability of the target's selection. The activation of the semantic network produces priming benefits during encoding, and search costs during retrieval. In extralist cuing, recall is a negative function of cue-to-distractor strength, and a positive function of neighborhood density, cue-to-target strength, and target-to-cue strength. We show how these four measures derived from the network can be combined and used to predict memory performance. These measures play different roles in different tasks, indicating that the contribution of the semantic network varies with the context provided by the task. Finally, we evaluate spreading-activation and quantum-like entanglement explanations for the priming effects produced by neighborhood density.

Multimodal Feature Integration in the Angular Gyrus during Episodic and Semantic Retrieval

PubMed Central

Bonnici, Heidi M.; Richter, Franziska R.; Yazar, Yasemin

2016-01-01

Much evidence from distinct lines of investigation indicates the involvement of angular gyrus (AnG) in the retrieval of both episodic and semantic information, but the region's precise function and whether that function differs across episodic and semantic retrieval have yet to be determined. We used univariate and multivariate fMRI analysis methods to examine the role of AnG in multimodal feature integration during episodic and semantic retrieval. Human participants completed episodic and semantic memory tasks involving unimodal (auditory or visual) and multimodal (audio-visual) stimuli. Univariate analyses revealed the recruitment of functionally distinct AnG subregions during the retrieval of episodic and semantic information. Consistent with a role in multimodal feature integration during episodic retrieval, significantly greater AnG activity was observed during retrieval of integrated multimodal episodic memories compared with unimodal episodic memories. Multivariate classification analyses revealed that individual multimodal episodic memories could be differentiated in AnG, with classification accuracy tracking the vividness of participants' reported recollections, whereas distinct unimodal memories were represented in sensory association areas only. In contrast to episodic retrieval, AnG was engaged to a statistically equivalent degree during retrieval of unimodal and multimodal semantic memories, suggesting a distinct role for AnG during semantic retrieval. Modality-specific sensory association areas exhibited corresponding activity during both episodic and semantic retrieval, which mirrored the functional specialization of these regions during perception. The results offer new insights into the integrative processes subserved by AnG and its contribution to our subjective experience of remembering. SIGNIFICANCE STATEMENT Using univariate and multivariate fMRI analyses, we provide evidence that functionally distinct subregions of angular gyrus (AnG) contribute to the retrieval of episodic and semantic memories. Our multivariate pattern classifier could distinguish episodic memory representations in AnG according to whether they were multimodal (audio-visual) or unimodal (auditory or visual) in nature, whereas statistically equivalent AnG activity was observed during retrieval of unimodal and multimodal semantic memories. Classification accuracy during episodic retrieval scaled with the trial-by-trial vividness with which participants experienced their recollections. Therefore, the findings offer new insights into the integrative processes subserved by AnG and how its function may contribute to our subjective experience of remembering. PMID:27194327

Multimodal Feature Integration in the Angular Gyrus during Episodic and Semantic Retrieval.

PubMed

Bonnici, Heidi M; Richter, Franziska R; Yazar, Yasemin; Simons, Jon S

2016-05-18

Much evidence from distinct lines of investigation indicates the involvement of angular gyrus (AnG) in the retrieval of both episodic and semantic information, but the region's precise function and whether that function differs across episodic and semantic retrieval have yet to be determined. We used univariate and multivariate fMRI analysis methods to examine the role of AnG in multimodal feature integration during episodic and semantic retrieval. Human participants completed episodic and semantic memory tasks involving unimodal (auditory or visual) and multimodal (audio-visual) stimuli. Univariate analyses revealed the recruitment of functionally distinct AnG subregions during the retrieval of episodic and semantic information. Consistent with a role in multimodal feature integration during episodic retrieval, significantly greater AnG activity was observed during retrieval of integrated multimodal episodic memories compared with unimodal episodic memories. Multivariate classification analyses revealed that individual multimodal episodic memories could be differentiated in AnG, with classification accuracy tracking the vividness of participants' reported recollections, whereas distinct unimodal memories were represented in sensory association areas only. In contrast to episodic retrieval, AnG was engaged to a statistically equivalent degree during retrieval of unimodal and multimodal semantic memories, suggesting a distinct role for AnG during semantic retrieval. Modality-specific sensory association areas exhibited corresponding activity during both episodic and semantic retrieval, which mirrored the functional specialization of these regions during perception. The results offer new insights into the integrative processes subserved by AnG and its contribution to our subjective experience of remembering. Using univariate and multivariate fMRI analyses, we provide evidence that functionally distinct subregions of angular gyrus (AnG) contribute to the retrieval of episodic and semantic memories. Our multivariate pattern classifier could distinguish episodic memory representations in AnG according to whether they were multimodal (audio-visual) or unimodal (auditory or visual) in nature, whereas statistically equivalent AnG activity was observed during retrieval of unimodal and multimodal semantic memories. Classification accuracy during episodic retrieval scaled with the trial-by-trial vividness with which participants experienced their recollections. Therefore, the findings offer new insights into the integrative processes subserved by AnG and how its function may contribute to our subjective experience of remembering. Copyright © 2016 Bonnici, Richter, et al.

Neuroanatomic organization of sound memory in humans.

PubMed

Kraut, Michael A; Pitcock, Jeffery A; Calhoun, Vince; Li, Juan; Freeman, Thomas; Hart, John

2006-11-01

The neural interface between sensory perception and memory is a central issue in neuroscience, particularly initial memory organization following perceptual analyses. We used functional magnetic resonance imaging to identify anatomic regions extracting initial auditory semantic memory information related to environmental sounds. Two distinct anatomic foci were detected in the right superior temporal gyrus when subjects identified sounds representing either animals or threatening items. Threatening animal stimuli elicited signal changes in both foci, suggesting a distributed neural representation. Our results demonstrate both category- and feature-specific responses to nonverbal sounds in early stages of extracting semantic memory information from these sounds. This organization allows for these category-feature detection nodes to extract early, semantic memory information for efficient processing of transient sound stimuli. Neural regions selective for threatening sounds are similar to those of nonhuman primates, demonstrating semantic memory organization for basic biological/survival primitives are present across species.

Cognitive training of self-initiation of semantic encoding strategies in schizophrenia: A pilot study.

PubMed

Guimond, Synthia; Lepage, Martin

2016-01-01

Available cognitive remediation interventions have a significant but relatively small to moderate impact on episodic memory in schizophrenia. The present study aimed to evaluate the efficacy and feasibility of a brief novel episodic memory training targeting the self-initiation of semantic encoding strategies. To select patients with such deficits, 28 participants with schizophrenia performed our Semantic Encoding Memory Task (SEMT) that provides a measure of self-initiated semantic encoding strategies. This task identified a deficit in 13 participants who were then offered two 60-minute training sessions one week apart. After the training, patients performed an alternate version of the SEMT. The CVLT-II (a standardised measure of semantic encoding strategies) and the BVMT-R (a control spatial memory task) were used to quantify memory pre- and post-training. After the training, participants were significantly better at self-initiating semantic encoding strategies in the SEMT (p = .004) and in the CVLT-II (p = .002). No significant differences were found in the BVMT-R. The current study demonstrates that a brief and specific training in memory strategies can help patients to improve a deficient memory process in schizophrenia. Future studies will need to test this intervention further using a randomised controlled trial, and to explore its functional impact.

Abnormal object recall and anterior cingulate overactivation correlate with formal thought disorder in schizophrenia.

PubMed

Assaf, Michal; Rivkin, Paul R; Kuzu, Cheedem H; Calhoun, Vince D; Kraut, Michael A; Groth, Karyn M; Yassa, Michael A; Hart, John; Pearlson, Godfrey D

2006-03-01

The neural basis of formal thought disorder (FTD) is unknown. An influential theory is that FTD results from impaired semantic memory processing. We explored the neural correlates of semantic memory retrieval in schizophrenia using an imaging task assessing semantic object recall. Sixteen healthy control subjects and sixteen schizophrenia patients whose FTD symptoms were measured with the Thought Disorder Index completed a verbal object-recall task during functional magnetic resonance imaging. Participants viewed two words describing object features that either evoked (object recall) or did not evoke a semantic concept. Schizophrenia patients tended to overrecall objects for feature pairs that did not describe the same object. Functionally, rostral anterior cingulate cortex (ACC) activation in patients positively correlated with FTD severity during both correct recalled and overrecalled trials. Compared with control subjects, during object recalling, patients overactivated bilateral ACC, temporooccipital junctions, temporal poles and parahippocampi, right inferior frontal gyrus, and dorsolateral prefrontal cortex, but underactivated inferior parietal lobules. Our results support impaired semantic memory retrieval as underlying FTD pathophysiology. Schizophrenia patients showed abnormal activations of brain areas involved in semantic memory, verbal working memory, and initiation and suppression of conflicting responses, which were associated with semantic overrecall and FTD.

Semantic memory in developmental amnesia.

PubMed

Elward, Rachael L; Vargha-Khadem, Faraneh

2018-04-30

Patients with developmental amnesia resulting from bilateral hippocampal atrophy associated with neonatal hypoxia-ischaemia typically show relatively preserved semantic memory and factual knowledge about the natural world despite severe impairments in episodic memory. Understanding the neural and mnemonic processes that enable this context-free semantic knowledge to be acquired throughout development without the support of the contextualised episodic memory system is a serious challenge. This review describes the clinical presentation of patients with developmental amnesia, contrasts its features with those reported for adult-onset hippocampal amnesia, and analyses the effects of variables that influence the learning of new semantic information. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Self-imagination can enhance memory in individuals with schizophrenia.

PubMed

Raffard, Stéphane; Bortolon, Catherine; Burca, Mariana; Novara, Caroline; Gely-Nargeot, Marie-Christine; Capdevielle, Delphine; Van der Linden, Martial

2016-01-01

Previous research has demonstrated that self-referential strategies can be applied to improve memory in various memory- impaired populations. However, little is known regarding the relative effectiveness of self-referential strategies in schizophrenia patients. The main aim of this study was to assess the effectiveness of a new self-referential strategy known as self- imagination (SI) on a free recall task. Twenty schizophrenia patients and 20 healthy controls intentionally encoded words under five instructions: superficial processing, semantic processing, semantic self-referential processing, episodic self-referential processing and semantic self- imagining. Other measures included depression, psychotic symptoms and cognitive measures. We found a SI effect in memory as self- imagining resulted in better performance in memory retrieval than semantic and superficial encoding in schizophrenia patients. The memory boost for self-referenced information in comparison to semantic processing was not found for other self-referential strategies. In addition no relationship between clinical variables and free recall performances was found. In controls, the SI condition did not result in better performance. The three self-referential strategies yielded better free recall than both superficial and semantic encoding. This study provides evidence of the clinical utility of self-imagining as a mnemonic strategy in schizophrenia patients.

Semantic strategy training increases memory performance and brain activity in patients with prefrontal cortex lesions.

PubMed

Miotto, Eliane C; Savage, Cary R; Evans, Jonathan J; Wilson, Barbara A; Martin, Maria G M; Balardin, Joana B; Barros, Fabio G; Garrido, Griselda; Teixeira, Manoel J; Amaro Junior, Edson

2013-03-01

Memory deficit is a frequent cognitive disorder following acquired prefrontal cortex lesions. In the present study, we investigated the brain correlates of a short semantic strategy training and memory performance of patients with distinct prefrontal cortex lesions using fMRI and cognitive tests. Twenty-one adult patients with post-acute prefrontal cortex (PFC) lesions, twelve with left dorsolateral PFC (LPFC) and nine with bilateral orbitofrontal cortex (BOFC) were assessed before and after a short cognitive semantic training using a verbal memory encoding paradigm during scanning and neuropsychological tests outside the scanner. After the semantic strategy training both groups of patients showed significant behavioral improvement in verbal memory recall and use of semantic strategies. In the LPFC group, greater activity in left inferior and medial frontal gyrus, precentral gyrus and insula was found after training. For the BOFC group, a greater activation was found in the left parietal cortex, right cingulated and precuneus after training. The activation of these specific areas in the memory and executive networks following cognitive training was associated to compensatory brain mechanisms and application of the semantic strategy. Copyright © 2012 Elsevier B.V. All rights reserved.

Post-Training Intrahippocampal Inhibition of Class I Histone Deacetylases Enhances Long-Term Object-Location Memory

ERIC Educational Resources Information Center

Hawk, Joshua D.; Florian, Cedrick; Abel, Ted

2011-01-01

Long-term memory formation involves covalent modification of the histone proteins that package DNA. Reducing histone acetylation by mutating histone acetyltransferases impairs long-term memory, and enhancing histone acetylation by inhibiting histone deacetylases (HDACs) improves long-term memory. Previous studies using HDAC inhibitors to enhance…

Long-Term Semantic Priming of Word Meaning

ERIC Educational Resources Information Center

Woltz, Dan J.

2010-01-01

Three experiments investigated facilitation in synonym decisions as a function of prior synonym decision trials that were either identical or semantically related. Experiment 1 demonstrated that semantically related prime trials produced less facilitation than identical prime trials, but facilitation from both persisted over 14 intervening trials.…

Insulin signaling is acutely required for long-term memory in Drosophila.

PubMed

Chambers, Daniel B; Androschuk, Alaura; Rosenfelt, Cory; Langer, Steven; Harding, Mark; Bolduc, Francois V

2015-01-01

Memory formation has been shown recently to be dependent on energy status in Drosophila. A well-established energy sensor is the insulin signaling (InS) pathway. Previous studies in various animal models including human have revealed the role of insulin levels in short-term memory but its role in long-term memory remains less clear. We therefore investigated genetically the spatial and temporal role of InS using the olfactory learning and long-term memory model in Drosophila. We found that InS is involved in both learning and memory. InS in the mushroom body is required for learning and long-term memory whereas long-term memory specifically is impaired after InS signaling disruption in the ellipsoid body, where it regulates the level of p70s6k, a downstream target of InS and a marker of protein synthesis. Finally, we show also that InS is acutely required for long-term memory formation in adult flies.

Physical exercise prevents short and long-term deficits on aversive and recognition memory and attenuates brain oxidative damage induced by maternal deprivation.

PubMed

Neves, Ben-Hur; Menezes, Jefferson; Souza, Mauren Assis; Mello-Carpes, Pâmela B

2015-12-01

It is known from previous research that physical exercise prevents long-term memory deficits induced by maternal deprivation in rats. But we could not assume similar effects of physical exercise on short-term memory, as short- and long-term memories are known to result from some different memory consolidation processes. Here we demonstrated that, in addition to long-term memory deficit, the short-term memory deficit resultant from maternal deprivation in object recognition and aversive memory tasks is also prevented by physical exercise. Additionally, one of the mechanisms by which the physical exercise influences the memory processes involves its effects attenuating the oxidative damage in the maternal deprived rats' hippocampus and prefrontal cortex.

Memory Dysfunction

PubMed Central

Matthews, Brandy R.

2015-01-01

Purpose of Review: This article highlights the dissociable human memory systems of episodic, semantic, and procedural memory in the context of neurologic illnesses known to adversely affect specific neuroanatomic structures relevant to each memory system. Recent Findings: Advances in functional neuroimaging and refinement of neuropsychological and bedside assessment tools continue to support a model of multiple memory systems that are distinct yet complementary and to support the potential for one system to be engaged as a compensatory strategy when a counterpart system fails. Summary: Episodic memory, the ability to recall personal episodes, is the subtype of memory most often perceived as dysfunctional by patients and informants. Medial temporal lobe structures, especially the hippocampal formation and associated cortical and subcortical structures, are most often associated with episodic memory loss. Episodic memory dysfunction may present acutely, as in concussion; transiently, as in transient global amnesia (TGA); subacutely, as in thiamine deficiency; or chronically, as in Alzheimer disease. Semantic memory refers to acquired knowledge about the world. Anterior and inferior temporal lobe structures are most often associated with semantic memory loss. The semantic variant of primary progressive aphasia (svPPA) is the paradigmatic disorder resulting in predominant semantic memory dysfunction. Working memory, associated with frontal lobe function, is the active maintenance of information in the mind that can be potentially manipulated to complete goal-directed tasks. Procedural memory, the ability to learn skills that become automatic, involves the basal ganglia, cerebellum, and supplementary motor cortex. Parkinson disease and related disorders result in procedural memory deficits. Most memory concerns warrant bedside cognitive or neuropsychological evaluation and neuroimaging to assess for specific neuropathologies and guide treatment. PMID:26039844

Olfactory memory in the old and very old: relations to episodic and semantic memory and APOE genotype.

PubMed

Larsson, Maria; Hedner, Margareta; Papenberg, Goran; Seubert, Janina; Bäckman, Lars; Laukka, Erika J

2016-02-01

The neuroanatomical organization that underlies olfactory memory is different from that of other memory types. The present work examines olfactory memory in an elderly population-based sample (Swedish National Study on Aging and Care in Kungsholmen) aged 60-100 years (n = 2280). We used structural equation modeling to investigate whether olfactory memory in old age is best conceptualized as a distinct category, differentiated from episodic and semantic memory. Further, potential olfactory dedifferentiation and genetic associations (APOE) to olfactory function in late senescence were investigated. Results are in support of a 3-factor solution where olfactory memory, as indexed by episodic odor recognition and odor identification, is modeled separately from episodic and semantic memory for visual and verbal information. Increasing age was associated with poorer olfactory memory performance, and observed age-related deficits were further exacerbated for carriers of the APOE ε4 allele; these effects tended to be larger for olfactory memory compared to episodic and semantic memory pertaining to other sensory systems (vision, auditory). Finally, stronger correlations between olfactory and episodic memory, indicating dedifferentiation, were observed in the older age groups. Copyright © 2016 Elsevier Inc. All rights reserved.

Semantic memory in object use.

PubMed

Silveri, Maria Caterina; Ciccarelli, Nicoletta

2009-10-01

We studied five patients with semantic memory disorders, four with semantic dementia and one with herpes simplex virus encephalitis, to investigate the involvement of semantic conceptual knowledge in object use. Comparisons between patients who had semantic deficits of different severity, as well as the follow-up, showed that the ability to use objects was largely preserved when the deficit was mild but progressively decayed as the deficit became more severe. Naming was generally more impaired than object use. Production tasks (pantomime execution and actual object use) and comprehension tasks (pantomime recognition and action recognition) as well as functional knowledge about objects were impaired when the semantic deficit was severe. Semantic and unrelated errors were produced during object use, but actions were always fluent and patients performed normally on a novel tools task in which the semantic demand was minimal. Patients with severe semantic deficits scored borderline on ideational apraxia tasks. Our data indicate that functional semantic knowledge is crucial for using objects in a conventional way and suggest that non-semantic factors, mainly non-declarative components of memory, might compensate to some extent for semantic disorders and guarantee some residual ability to use very common objects independently of semantic knowledge.

Auditory attention strategy depends on target linguistic properties and spatial configurationa)

PubMed Central

McCloy, Daniel R.; Lee, Adrian K. C.

2015-01-01

Whether crossing a busy intersection or attending a large dinner party, listeners sometimes need to attend to multiple spatially distributed sound sources or streams concurrently. How they achieve this is not clear—some studies suggest that listeners cannot truly simultaneously attend to separate streams, but instead combine attention switching with short-term memory to achieve something resembling divided attention. This paper presents two oddball detection experiments designed to investigate whether directing attention to phonetic versus semantic properties of the attended speech impacts listeners' ability to divide their auditory attention across spatial locations. Each experiment uses four spatially distinct streams of monosyllabic words, variation in cue type (providing phonetic or semantic information), and requiring attention to one or two locations. A rapid button-press response paradigm is employed to minimize the role of short-term memory in performing the task. Results show that differences in the spatial configuration of attended and unattended streams interact with linguistic properties of the speech streams to impact performance. Additionally, listeners may leverage phonetic information to make oddball detection judgments even when oddballs are semantically defined. Both of these effects appear to be mediated by the overall complexity of the acoustic scene. PMID:26233011

The word-length effect and disyllabic words.

PubMed

Lovatt, P; Avons, S E; Masterson, J

2000-02-01

Three experiments compared immediate serial recall of disyllabic words that differed on spoken duration. Two sets of long- and short-duration words were selected, in each case maximizing duration differences but matching for frequency, familiarity, phonological similarity, and number of phonemes, and controlling for semantic associations. Serial recall measures were obtained using auditory and visual presentation and spoken and picture-pointing recall. In Experiments 1a and 1b, using the first set of items, long words were better recalled than short words. In Experiments 2a and 2b, using the second set of items, no difference was found between long and short disyllabic words. Experiment 3 confirmed the large advantage for short-duration words in the word set originally selected by Baddeley, Thomson, and Buchanan (1975). These findings suggest that there is no reliable advantage for short-duration disyllables in span tasks, and that previous accounts of a word-length effect in disyllables are based on accidental differences between list items. The failure to find an effect of word duration casts doubt on theories that propose that the capacity of memory span is determined by the duration of list items or the decay rate of phonological information in short-term memory.

An Account of Performance in Accessing Information Stored in Long-Term Memory. A Fixed-Links Model Approach

ERIC Educational Resources Information Center

Altmeyer, Michael; Schweizer, Karl; Reiss, Siegbert; Ren, Xuezhu; Schreiner, Michael

2013-01-01

Performance in working memory and short-term memory tasks was employed for predicting performance in a long-term memory task in order to find out about the underlying processes. The types of memory were represented by versions of the Posner Task, the Backward Counting Task and the Sternberg Task serving as measures of long-term memory, working…

Prefrontal θ-Burst Stimulation Disrupts the Organizing Influence of Active Short-Term Retrieval on Episodic Memory.

PubMed

Marin, Bianca M; VanHaerents, Stephen A; Voss, Joel L; Bridge, Donna J

2018-01-01

Dorsolateral prefrontal cortex (DLPFC) is thought to organize items in working memory and this organizational role may also influence long-term memory. To causally test this hypothesized role of DLPFC in long-term memory formation, we used θ-burst noninvasive stimulation (TBS) to modulate DLPFC involvement in a memory task that assessed the influence of active short-term retrieval on later memory. Human subjects viewed three objects on a grid and then either actively retrieved or passively restudied one object's location after a brief delay. Long-term memory for the other objects was assessed after a delay to evaluate the beneficial role of active short-term retrieval on subsequent memory for the entire set of object locations. We found that DLPFC TBS had no significant effects on short-term memory. In contrast, DLPFC TBS impaired long-term memory selectively in the active-retrieval condition but not in the passive-restudy condition. These findings are consistent with the hypothesized contribution of DLPFC to the organizational processes operative during active short-term retrieval that influence long-term memory, although other regions that were not stimulated could provide similar contributions. Notably, active-retrieval and passive-restudy conditions were intermixed, and therefore nonspecific influences of stimulation were well controlled. These results suggest that DLPFC is causally involved in organizing event information during active retrieval to support coherent long-term memory formation.

Prefrontal θ-Burst Stimulation Disrupts the Organizing Influence of Active Short-Term Retrieval on Episodic Memory

PubMed Central

2018-01-01

Abstract Dorsolateral prefrontal cortex (DLPFC) is thought to organize items in working memory and this organizational role may also influence long-term memory. To causally test this hypothesized role of DLPFC in long-term memory formation, we used θ-burst noninvasive stimulation (TBS) to modulate DLPFC involvement in a memory task that assessed the influence of active short-term retrieval on later memory. Human subjects viewed three objects on a grid and then either actively retrieved or passively restudied one object’s location after a brief delay. Long-term memory for the other objects was assessed after a delay to evaluate the beneficial role of active short-term retrieval on subsequent memory for the entire set of object locations. We found that DLPFC TBS had no significant effects on short-term memory. In contrast, DLPFC TBS impaired long-term memory selectively in the active-retrieval condition but not in the passive-restudy condition. These findings are consistent with the hypothesized contribution of DLPFC to the organizational processes operative during active short-term retrieval that influence long-term memory, although other regions that were not stimulated could provide similar contributions. Notably, active-retrieval and passive-restudy conditions were intermixed, and therefore nonspecific influences of stimulation were well controlled. These results suggest that DLPFC is causally involved in organizing event information during active retrieval to support coherent long-term memory formation. PMID:29445769

Complex network structure influences processing in long-term and short-term memory.

PubMed

Vitevitch, Michael S; Chan, Kit Ying; Roodenrys, Steven

2012-07-01

Complex networks describe how entities in systems interact; the structure of such networks is argued to influence processing. One measure of network structure, clustering coefficient, C, measures the extent to which neighbors of a node are also neighbors of each other. Previous psycholinguistic experiments found that the C of phonological word-forms influenced retrieval from the mental lexicon (that portion of long-term memory dedicated to language) during the on-line recognition and production of spoken words. In the present study we examined how network structure influences other retrieval processes in long- and short-term memory. In a false-memory task-examining long-term memory-participants falsely recognized more words with low- than high-C. In a recognition memory task-examining veridical memories in long-term memory-participants correctly recognized more words with low- than high-C. However, participants in a serial recall task-examining redintegration in short-term memory-recalled lists comprised of high-C words more accurately than lists comprised of low-C words. These results demonstrate that network structure influences cognitive processes associated with several forms of memory including lexical, long-term, and short-term.

Working memory, long-term memory, and medial temporal lobe function

PubMed Central

Jeneson, Annette; Squire, Larry R.

2012-01-01

Early studies of memory-impaired patients with medial temporal lobe (MTL) damage led to the view that the hippocampus and related MTL structures are involved in the formation of long-term memory and that immediate memory and working memory are independent of these structures. This traditional idea has recently been revisited. Impaired performance in patients with MTL lesions on tasks with short retention intervals, or no retention interval, and neuroimaging findings with similar tasks have been interpreted to mean that the MTL is sometimes needed for working memory and possibly even for visual perception itself. We present a reappraisal of this interpretation. Our main conclusion is that, if the material to be learned exceeds working memory capacity, if the material is difficult to rehearse, or if attention is diverted, performance depends on long-term memory even when the retention interval is brief. This fundamental notion is better captured by the terms subspan memory and supraspan memory than by the terms short-term memory and long-term memory. We propose methods for determining when performance on short-delay tasks must depend on long-term (supraspan) memory and suggest that MTL lesions impair performance only when immediate memory and working memory are insufficient to support performance. In neuroimaging studies, MTL activity during encoding is influenced by the memory load and correlates positively with long-term retention of the material that was presented. The most parsimonious and consistent interpretation of all the data is that subspan memoranda are supported by immediate memory and working memory and are independent of the MTL. PMID:22180053

Modulation of working memory updating: Does long-term memory lexical association matter?

PubMed

Artuso, Caterina; Palladino, Paola

2016-02-01

The aim of the present study was to investigate how working memory updating for verbal material is modulated by enduring properties of long-term memory. Two coexisting perspectives that account for the relation between long-term representation and short-term performance were addressed. First, evidence suggests that performance is more closely linked to lexical properties, that is, co-occurrences within the language. Conversely, other evidence suggests that performance is linked more to long-term representations which do not entail lexical/linguistic representations. Our aim was to investigate how these two kinds of long-term memory associations (i.e., lexical or nonlexical) modulate ongoing working memory activity. Therefore, we manipulated (between participants) the strength of the association in letters based on either frequency of co-occurrences (lexical) or contiguity along the sequence of the alphabet (nonlexical). Results showed a cost in working memory updating for strongly lexically associated stimuli only. Our findings advance knowledge of how lexical long-term memory associations between consonants affect working memory updating and, in turn, contribute to the study of factors which impact the updating process across memory systems.

Mechanisms underlying the production of false memories for famous people's names in aging and Alzheimer's disease.

PubMed

Plancher, Gaën; Guyard, Anne; Nicolas, Serge; Piolino, Pascale

2009-10-01

It is well known that the occurrence of false memories increases with aging, but the results remain inconsistent concerning Alzheimer's disease (AD). Moreover, the mechanisms underlying the production of false memories are still unclear. Using an experimental episodic memory test with material based on the names of famous people in a procedure derived from the DRM paradigm [Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory & Cognition, 21, 803-814], we examined correct and false recall and recognition in 30 young adults, 40 healthy older adults, and 30 patients with AD. Moreover, we evaluated the relationships between false memory performance, correct episodic memory performance, and a set of neuropsychological assessments evaluating the semantic memory and executive functions. The results clearly indicated that correct recall and recognition performance decreased with the subjects' age, but it decreased even more with AD. In addition, semantically related false recalls and false recognitions increased with age but not with dementia. On the contrary, non-semantically related false recalls and false recognitions increased with AD. Finally, the regression analyses showed that executive functions mediated related false memories and episodic memory mediated related and unrelated false memories in aging. Moreover, executive functions predicted related and unrelated false memories in AD, and episodic and semantic memory predicted semantically related and unrelated false memories in AD. In conclusion, the results obtained are consistent with the current constructive models of memory suggesting that false memory creation depends on different cognitive functions and, consequently, that the impairments of these functions influence the production of false memories.

Right inferior frontal gyrus activation is associated with memory improvement in patients with left frontal low-grade glioma resection.

PubMed

Miotto, Eliane C; Balardin, Joana B; Vieira, Gilson; Sato, Joao R; Martin, Maria da Graça M; Scaff, Milberto; Teixeira, Manoel J; Junior, Edson Amaro

2014-01-01

Patients with low-grade glioma (LGG) have been studied as a model of functional brain reorganization due to their slow-growing nature. However, there is no information regarding which brain areas are involved during verbal memory encoding after extensive left frontal LGG resection. In addition, it remains unknown whether these patients can improve their memory performance after instructions to apply efficient strategies. The neural correlates of verbal memory encoding were investigated in patients who had undergone extensive left frontal lobe (LFL) LGG resections and healthy controls using fMRI both before and after directed instructions were given for semantic organizational strategies. Participants were scanned during the encoding of word lists under three different conditions before and after a brief period of practice. The conditions included semantically unrelated (UR), related-non-structured (RNS), and related-structured words (RS), allowing for different levels of semantic organization. All participants improved on memory recall and semantic strategy application after the instructions for the RNS condition. Healthy subjects showed increased activation in the left inferior frontal gyrus (IFG) and middle frontal gyrus (MFG) during encoding for the RNS condition after the instructions. Patients with LFL excisions demonstrated increased activation in the right IFG for the RNS condition after instructions were given for the semantic strategies. Despite extensive damage in relevant areas that support verbal memory encoding and semantic strategy applications, patients that had undergone resections for LFL tumor could recruit the right-sided contralateral homologous areas after instructions were given and semantic strategies were practiced. These results provide insights into changes in brain activation areas typically implicated in verbal memory encoding and semantic processing.

Distinct neuroanatomical bases of episodic and semantic memory performance in Alzheimer's disease.

PubMed

Hirni, Daniela I; Kivisaari, Sasa L; Monsch, Andreas U; Taylor, Kirsten I

2013-04-01

Alzheimer's disease (AD) neurofibrillary pathology begins in the medial perirhinal cortex (mPRC) before spreading to the entorhinal cortex (ERC) and hippocampus (HP) in anterior medial temporal lobe (aMTL). While the role of the ERC/HP complex in episodic memory formation is well-established, recent research suggests that the PRC is required to form semantic memories of individual objects. We aimed to test whether commonly used clinical measures of episodic and semantic memory are distinctly associated with ERC/HP and mPRC integrity, respectively, in healthy mature individuals and very early AD patients. One hundred thirty normal controls, 32 amnestic mild cognitive impairment patients, some of whom are in the earliest (i.e., preclinical) stages of AD, and ten early-stage AD patients received neuropsychological testing and high-resolution anatomic and diffusion MRI. Voxel-based regression analyses tested for regions where episodic memory (delayed recall scores on the California Verbal Learning and Rey Osterrieth Complex Figure Tests) and semantic memory (Boston Naming Test, category fluency) performance correlated with gray matter (GM) regions of interest and whole-brain fractional anisotropy (FA) voxel values. When controlling for the opposing memory performance, poorer episodic memory performance was associated with reduced bilateral ERC/HP GM volume and related white matter integrity, but not with mPRC GM volume. Poor semantic memory performance was associated with both reduced left mPRC and ERC/HP GM volume, as well as reduced FA values in white matter tracts leading to the PRC. These results indicate a partial division of labor within the aMTL and suggest that mPRC damage in very early AD may be detectable with common clinical tests of semantic memory if episodic memory performance is controlled. Copyright © 2013 Elsevier Ltd. All rights reserved.

Clues for minimal hepatic encephalopathy in children with noncirrhotic portal hypertension.

PubMed

D'Antiga, Lorenzo; Dacchille, Patrizia; Boniver, Clementina; Poledri, Sara; Schiff, Sami; Zancan, Lucia; Amodio, Piero

2014-12-01

In children with noncirrhotic extrahepatic portal vein obstruction (EHPVO), minimal hepatic encephalopathy (MHE) was reported in a few series, but neither is it routinely investigated nor does consensus about its diagnosis exist. In this prospective observational study we aimed at detecting the prevalence of MHE in children with EHPVO and providing a practical diagnostic protocol. A consecutive sample of 13 noncirrhotic children (age range 4-18 years) with EHPVO underwent a screening for MHE based on level of fasting ammonia, quantified electroencephalogram (EEG) evaluation, and a wide battery of 26 psychometric tests exploring learning ability, abstract reasoning, phonemic and semantic fluency, selective attention, executive functions, short-term verbal and visual memory, long-term verbal memory, and visuopractic ability. Five children had at least 2 altered psychometric tests. Selective attention, executive function, and short-term visual memory were the domains more frequently altered, and 4 tests were enough to detect 80% of these children. Fasting ammonia plasma level was increased in 6 children. EEG mean dominant frequency adjusted for age was associated with serum ammonia concentration (β = -0.44 ± 0.19, P < 0.05). As a whole, children with EHPVO showed trends for lower α (median 41% vs 49%) and higher θ power than controls (median 41% vs 49% and 29% vs 20%, respectively). MHE affects approximately 50% of children with EHPVO and, therefore, is worthwhile to be investigated. Three simple tools, serum ammonia, quantified EEG, and neuropsychological examination, focused on selective attention, executive function, and short-term visual memory can be used effectively in the evaluation of MHE in this setting.

Processing of visual semantic information to concrete words: temporal dynamics and neural mechanisms indicated by event-related brain potentials( ).

PubMed

van Schie, Hein T; Wijers, Albertus A; Mars, Rogier B; Benjamins, Jeroen S; Stowe, Laurie A

2005-05-01

Event-related brain potentials were used to study the retrieval of visual semantic information to concrete words, and to investigate possible structural overlap between visual object working memory and concreteness effects in word processing. Subjects performed an object working memory task that involved 5 s retention of simple 4-angled polygons (load 1), complex 10-angled polygons (load 2), and a no-load baseline condition. During the polygon retention interval subjects were presented with a lexical decision task to auditory presented concrete (imageable) and abstract (nonimageable) words, and pseudowords. ERP results are consistent with the use of object working memory for the visualisation of concrete words. Our data indicate a two-step processing model of visual semantics in which visual descriptive information of concrete words is first encoded in semantic memory (indicated by an anterior N400 and posterior occipital positivity), and is subsequently visualised via the network for object working memory (reflected by a left frontal positive slow wave and a bilateral occipital slow wave negativity). Results are discussed in the light of contemporary models of semantic memory.

Long-term associative learning predicts verbal short-term memory performance.

PubMed

Jones, Gary; Macken, Bill

2018-02-01

Studies using tests such as digit span and nonword repetition have implicated short-term memory across a range of developmental domains. Such tests ostensibly assess specialized processes for the short-term manipulation and maintenance of information that are often argued to enable long-term learning. However, there is considerable evidence for an influence of long-term linguistic learning on performance in short-term memory tasks that brings into question the role of a specialized short-term memory system separate from long-term knowledge. Using natural language corpora, we show experimentally and computationally that performance on three widely used measures of short-term memory (digit span, nonword repetition, and sentence recall) can be predicted from simple associative learning operating on the linguistic environment to which a typical child may have been exposed. The findings support the broad view that short-term verbal memory performance reflects the application of long-term language knowledge to the experimental setting.

Autobiographical memory and well-being in aging: The central role of semantic self-images.

PubMed

Rathbone, Clare J; Holmes, Emily A; Murphy, Susannah E; Ellis, Judi A

2015-05-01

Higher levels of well-being are associated with longer life expectancies and better physical health. Previous studies suggest that processes involving the self and autobiographical memory are related to well-being, yet these relationships are poorly understood. The present study tested 32 older and 32 younger adults using scales measuring well-being and the affective valence of two types of autobiographical memory: episodic autobiographical memories and semantic self-images. Results showed that valence of semantic self-images, but not episodic autobiographical memories, was highly correlated with well-being, particularly in older adults. In contrast, well-being in older adults was unrelated to performance across a range of standardised memory tasks. These results highlight the role of semantic self-images in well-being, and have implications for the development of therapeutic interventions for well-being in aging. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Levels of processing and language modality specificity in working memory.

PubMed

Rudner, Mary; Karlsson, Thomas; Gunnarsson, Johan; Rönnberg, Jerker

2013-03-01

Neural networks underpinning working memory demonstrate sign language specific components possibly related to differences in temporary storage mechanisms. A processing approach to memory systems suggests that the organisation of memory storage is related to type of memory processing as well. In the present study, we investigated for the first time semantic, phonological and orthographic processing in working memory for sign- and speech-based language. During fMRI we administered a picture-based 2-back working memory task with Semantic, Phonological, Orthographic and Baseline conditions to 11 deaf signers and 20 hearing non-signers. Behavioural data showed poorer and slower performance for both groups in Phonological and Orthographic conditions than in the Semantic condition, in line with depth-of-processing theory. An exclusive masking procedure revealed distinct sign-specific neural networks supporting working memory components at all three levels of processing. The overall pattern of sign-specific activations may reflect a relative intermodality difference in the relationship between phonology and semantics influencing working memory storage and processing. Copyright © 2012 Elsevier Ltd. All rights reserved.

Visual long-term memory has the same limit on fidelity as visual working memory.

PubMed

Brady, Timothy F; Konkle, Talia; Gill, Jonathan; Oliva, Aude; Alvarez, George A

2013-06-01

Visual long-term memory can store thousands of objects with surprising visual detail, but just how detailed are these representations, and how can one quantify this fidelity? Using the property of color as a case study, we estimated the precision of visual information in long-term memory, and compared this with the precision of the same information in working memory. Observers were shown real-world objects in random colors and were asked to recall the colors after a delay. We quantified two parameters of performance: the variability of internal representations of color (fidelity) and the probability of forgetting an object's color altogether. Surprisingly, the fidelity of color information in long-term memory was comparable to the asymptotic precision of working memory. These results suggest that long-term memory and working memory may be constrained by a common limit, such as a bound on the fidelity required to retrieve a memory representation.

'In the course of time': a PET study of the cerebral substrates of autobiographical amnesia in Alzheimer's disease.

PubMed

Eustache, Francis; Piolino, Pascale; Giffard, Bénédicte; Viader, Fausto; De La Sayette, Vincent; Baron, Jean-Claude; Desgranges, Béatrice

2004-07-01

Neuroimaging studies in healthy subjects have yielded controversial results about the neural substrates of autobiographical memory. Moreover, the neural networks responsible for autobiographical amnesia remain poorly understood. Since autobiographical memory is frequently altered in Alzheimer's disease (AD), we used this degenerative disorder as a model and applied a correlative approach between resting cerebral glucose utilization (CMRGlc) and temporally graded memory scores to identify the cerebral structures whose synaptic dysfunction subserves the impairment in autobiographical memory. To this end, we studied a group of 17 AD patients with mild to moderate dementia in whom autobiographical memory was assessed using a specially designed task from three broad time periods [the previous 5 years (period A); middle age (period B); and teenage and childhood (period C)], and measures of resting CMRGlc were obtained with PET. The patients performed less well than a control group for all three time periods and showed the expected temporal gradient, with the most remote period being best preserved (Ribot's gradient). Qualitative analysis showed that remote memories concerned generic (i.e. semantic) rather than specific (i.e. episodic) events. We found a significant positive correlation between autobiographical scores and the metabolism of the right hippocampus (extending to the lingual gyrus), restricted to period A. In addition, period A scores were significantly correlated with the right middle and inferior frontal gyri and the right middle temporal gyrus. Period B scores correlated chiefly with the prefrontal cortex bilaterally (bilateral superior, bilateral middle and right inferior gyri). Metabolic correlations with period C scores were restricted to the left middle frontal gyrus. These findings show striking differences in metabolic correlations with the autobiographical time period, in agreement with prevalent theories of normal functioning of human memory. Thus, in accordance with theories of long-term memory consolidation, we find the expected implication of the hippocampal region in the recall of recent memories, and a disengagement of this structure when the retention interval is beyond 5 years. Moreover, according to the hemispheric encoding/retrieval asymmetry model based on activation studies in healthy subjects, the fact that recent memories preferentially involved the right prefrontal cortex whereas remote memories involved the left prefrontal cortex supports the notion of semanticization of memories with time interval, such that preserved remote memories in AD have a predominantly semantic character. Copyright 2004 Guarantors of Brain

MDMA (Ecstasy) use is associated with reduced BOLD signal change during semantic recognition in abstinent human polydrug users: a preliminary fMRI study

PubMed Central

Raj, Vidya; Liang, Han-Chun; Woodward, Neil D.; Bauernfeind, Amy L.; Lee, Junghee; Dietrich, Mary; Park, Sohee; Cowan, Ronald L.

2011-01-01

Objectives MDMA users have impaired verbal memory, and voxel-based morphometry has demonstrated decreased gray matter in Brodmann area (BA) 18, 21 and 45. Because these regions play a role in verbal memory, we hypothesized that MDMA users would show altered brain activation in these areas during performance of an fMRI task that probed semantic verbal memory. Methods Polysubstance users enriched for MDMA exposure participated in a semantic memory encoding and recognition fMRI task that activated left BA 9, 18, 21/22 and 45. Primary outcomes were percent BOLD signal change in left BA 9, 18, 21/22 and 45, accuracy and response time. Results During semantic recognition, lifetime MDMA use was associated with decreased activation in left BA 9, 18 and 21/22 but not 45. This was partly influenced by contributions from cannabis and cocaine use. MDMA exposure was not associated with accuracy or response time during the semantic recognition task. Conclusions During semantic recognition, MDMA exposure is associated with reduced regional brain activation in regions mediating verbal memory. These findings partially overlap with prior structural evidence for reduced gray matter in MDMA users and may, in part, explain the consistent verbal memory impairments observed in other studies of MDMA users. PMID:19304866

A role for autophagy in long-term spatial memory formation in male rodents.

PubMed

Hylin, Michael J; Zhao, Jing; Tangavelou, Karthikeyan; Rozas, Natalia S; Hood, Kimberly N; MacGowan, Jacalyn S; Moore, Anthony N; Dash, Pramod K

2018-03-01

A hallmark of long-term memory formation is the requirement for protein synthesis. Administration of protein synthesis inhibitors impairs long-term memory formation without influencing short-term memory. Rapamycin is a specific inhibitor of target of rapamycin complex 1 (TORC1) that has been shown to block protein synthesis and impair long-term memory. In addition to regulating protein synthesis, TORC1 also phosphorylates Unc-51-like autophagy activating kinase-1 (Ulk-1) to suppress autophagy. As autophagy can be activated by rapamycin (and rapamycin inhibits long-term memory), our aim was to test the hypothesis that autophagy inhibitors would enhance long-term memory. To examine if learning alters autophagosome number, we used male reporter mice carrying the GFP-LC3 transgene. Using these mice, we observed that training in the Morris water maze task increases the number of autophagosomes, a finding contrary to our expectations. For learning and memory studies, male Long Evans rats were used due to their relatively larger size (compared to mice), making it easier to perform intrahippocampal infusions in awake, moving animals. When the autophagy inhibitors 3-methyladenine (3-MA) or Spautin-1 were administered bilaterally into the hippocampii prior to training in the Morris water maze task, the drugs did not alter learning. In contrast, when memory was tested 24 hours later by a probe trial, significant impairments were observed. In addition, intrahippocampal infusion of an autophagy activator peptide (TAT-Beclin-1) improved long-term memory. These results indicate that autophagy is not necessary for learning, but is required for long-term memory formation. © 2017 Wiley Periodicals, Inc.

Divided attention can enhance memory encoding: the attentional boost effect in implicit memory.

PubMed

Spataro, Pietro; Mulligan, Neil W; Rossi-Arnaud, Clelia

2013-07-01

Distraction during encoding has long been known to disrupt later memory performance. Contrary to this long-standing result, we show that detecting an infrequent target in a dual-task paradigm actually improves memory encoding for a concurrently presented word, above and beyond the performance reached in the full-attention condition. This absolute facilitation was obtained in 2 perceptual implicit tasks (lexical decision and word fragment completion) but not in a conceptual implicit task (semantic classification). In the case of recognition memory, the facilitation was relative, bringing accuracy in the divided attention condition up to the level of accuracy in the full attention condition. The findings follow from the hypothesis that the attentional boost effect reflects enhanced visual encoding of the study stimulus consequent to the transient orienting response to the dual-task target. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Knowing what from where: Hippocampal connectivity with temporoparietal cortex at rest is linked to individual differences in semantic and topographic memory.

PubMed

Sormaz, Mladen; Jefferies, Elizabeth; Bernhardt, Boris C; Karapanagiotidis, Theodoros; Mollo, Giovanna; Bernasconi, Neda; Bernasconi, Andrea; Hartley, Tom; Smallwood, Jonathan

2017-05-15

The hippocampus contributes to episodic, spatial and semantic aspects of memory, yet individual differences within and between these functions are not well-understood. In 136 healthy individuals, we investigated whether these differences reflect variation in the strength of connections between functionally-specialised segments of the hippocampus and diverse cortical regions that participate in different aspects of memory. Better topographical memory was associated with stronger connectivity between lingual gyrus and left anterior, rather than posterior, hippocampus. Better semantic memory was associated with increased connectivity between the intracalcarine/cuneus and left, rather than right, posterior hippocampus. Notably, we observed a double dissociation between semantic and topographical memory: better semantic memory was associated with stronger connectivity between left temporoparietal cortex and left anterior hippocampus, while better topographic memory was linked to stronger connectivity with right anterior hippocampus. Together these data support a division-of-labour account of hippocampal functioning: at the population level, differences in connectivity across the hippocampus reflect functional specialisation for different facets of memory, while variation in these connectivity patterns across individuals is associated with differences in the capacity to retrieve different types of information. In particular, within-hemisphere connectivity between hippocampus and left temporoparietal cortex supports conceptual processing at the expense of spatial ability. Copyright © 2017. Published by Elsevier Inc.

Recall of remote episodic memory in amnesia.

PubMed

Zola-Morgan, S; Cohen, N J; Squire, L R

1983-01-01

Recall of remote episodic memory was assessed in three types of amnesic patient whose remote semantic memory had been evaluated previously. Patients with Korsakoff's syndrome, case N.A. and patients receiving electroconvulsive therapy all succeeded in recalling specific autobiographical episodes in response to single-word cues, and in many conditions performed as well as control subjects. Their pattern of performance generally paralleled that obtained in previous tests of remote semantic memory. These results argue against a view that amnesia reflects a selective deficit of episodic memory and suggest that the semantic-episodic distinction cannot illuminate the fundamental deficit in amnesia. Nor can the facts of amnesia confirm or deny the validity of this distinction in normal memory.

An Italian battery for the assessment of semantic memory disorders.

PubMed

Catricalà, Eleonora; Della Rosa, Pasquale A; Ginex, Valeria; Mussetti, Zoe; Plebani, Valentina; Cappa, Stefano F

2013-06-01

We report the construction and standardization of a new comprehensive battery of tests for the assessment of semantic memory disorders. The battery is constructed on a common set of 48 stimuli, belonging to both living and non-living categories, rigidly controlled for several confounding variables, and is based on an empirically derived corpus of semantic features. It includes six tasks, in order to assess semantic memory through different modalities of input and output: two naming tasks, one with colored pictures and the other in response to an oral description, a word-picture matching task, a picture sorting task, a free generation of features task and a sentence verification task. Normative data on 106 Italian subjects pooled across homogenous subgroups for age, sex and education are reported. The new battery allows an in-depth investigation of category-specific disorders and of progressive semantic memory deficits at features level, overcoming some of the limitations of existing tests.

Semantic and episodic memory of music are subserved by distinct neural networks.

PubMed

Platel, Hervé; Baron, Jean-Claude; Desgranges, Béatrice; Bernard, Frédéric; Eustache, Francis

2003-09-01

Numerous functional imaging studies have shown that retrieval from semantic and episodic memory is subserved by distinct neural networks. However, these results were essentially obtained with verbal and visuospatial material. The aim of this work was to determine the neural substrates underlying the semantic and episodic components of music using familiar and nonfamiliar melodic tunes. To study musical semantic memory, we designed a task in which the instruction was to judge whether or not the musical extract was felt as "familiar." To study musical episodic memory, we constructed two delayed recognition tasks, one containing only familiar and the other only nonfamiliar items. For each recognition task, half of the extracts (targets) were presented in the prior semantic task. The episodic and semantic tasks were to be contrasted by a comparison to two perceptive control tasks and to one another. Cerebral blood flow was assessed by means of the oxygen-15-labeled water injection method, using high-resolution PET. Distinct patterns of activations were found. First, regarding the episodic memory condition, bilateral activations of the middle and superior frontal gyri and precuneus (more prominent on the right side) were observed. Second, the semantic memory condition disclosed extensive activations in the medial and orbital frontal cortex bilaterally, the left angular gyrus, and predominantly the left anterior part of the middle temporal gyri. The findings from this study are discussed in light of the available neuropsychological data obtained in brain-damaged subjects and functional neuroimaging studies.

Heterogeneity in semantic priming effect with a lexical decision task in patients after left hemisphere stroke

PubMed Central

Holderbaum, Candice Steffen; Mansur, Letícia Lessa; de Salles, Jerusa Fumagalli

2016-01-01

ABSTRACT Investigations on the semantic priming effect (SPE) in patients after left hemisphere (LH) lesions have shown disparities that may be explained by the variability in performance found among patients. The aim of the present study was to verify the existence of subgroups of patients after LH stroke by searching for dissociations between performance on the lexical decision task based on the semantic priming paradigm and performance on direct memory, semantic association and language tasks. All 17 patients with LH lesions after stroke (ten non-fluent aphasics and seven non aphasics) were analyzed individually. Results indicated the presence of three groups of patients according to SPE: one exhibiting SPE at both stimulus onset asynchronies (SOAs), one with SPE only at long SOA, and another, larger group with no SPE. PMID:29213439

Intelligence related upper alpha desynchronization in a semantic memory task.

PubMed

Doppelmayr, M; Klimesch, W; Hödlmoser, K; Sauseng, P; Gruber, W

2005-07-30

Recent evidence shows that event-related (upper) alpha desynchronization (ERD) is related to cognitive performance. Several studies observed a positive, some a negative relationship. The latter finding, interpreted in terms of the neural efficiency hypothesis, suggests that good performance is associated with a more 'efficient', smaller extent of cortical activation. Other studies found that ERD increases with semantic processing demands and that this increase is larger for good performers. Studies supporting the neural efficiency hypothesis used tasks that do not specifically require semantic processing. Thus, we assume that the lack of semantic processing demands may at least in part be responsible for the reduced ERD. In the present study we measured ERD during a difficult verbal-semantic task. The findings demonstrate that during semantic processing, more intelligent (as compared to less intelligent) subjects exhibited a significantly larger upper alpha ERD over the left hemisphere. We conclude that more intelligent subjects exhibit a more extensive activation in a semantic processing system and suggest that divergent findings regarding the neural efficiency hypotheses are due to task specific differences in semantic processing demands.

The Categorical Structure of Semantic Memory for Famous People: A New Approach Using Release from Proactive Interference

ERIC Educational Resources Information Center

Darling, S.; Valentine, T.

2005-01-01

Memory for familiar people is essential to understand their identity and guide social interaction. Nevertheless, we know surprisingly little about the structure of such memory. Previous research has assumed that semantic memory for people has a categorical structure, but recently it was proposed that memory for people consists only of associations…

Semantic acquisition without memories: evidence from transient global amnesia.

PubMed

Guillery, B; Desgranges, B; Katis, S; de la Sayette, V; Viader, F; Eustache, F

2001-12-04

Transient global amnesia (TGA), characterised by a profound anterograde amnesia, is a model of interest to study the acquisition of novel meanings independent of episodic functioning. Three patients were tested during a TGA attack, two in the early recovery phase and the third during the acute phase of TGA, with a semantic priming task involving a restructuring process of conceptual knowledge. During TGA, all patients demonstrated priming effects. Results obtained the day after the episode with the same task showed that these effects persisted at least one day. Episodic memory seems not to be critical for the formation of novel connections among unrelated semantic representations, in accordance with Tulving's model of memory, i.e. episodic memory is not necessary for the acquisition of semantic information.

Episodic and Semantic Memory: Implications for the Role of Emotion in Advertising.

ERIC Educational Resources Information Center

Thorson, Esther

In an examination of the way people store and retrieve information from advertising, this paper draws a distinction between "semantic" memory, which stores general knowledge about the world, and "episodic" memory, which stores information about specific events. It then argues that episodic memory plays a more significant role…

Semantic Memory Recognition Is Supported by Intrinsic Recollection-Like Processes: "The Butcher on the Bus" Revisited

ERIC Educational Resources Information Center

Waidergoren, Shani; Segalowicz, Judith; Gilboa, Asaf

2012-01-01

Dual-process models suggest that recognition memory is independently supported by recollection and familiarity. Current theories attribute recollection solely to hippocampally mediated episodic memory (EM), and familiarity to both episodic and semantic memory (SM) supported by medial temporal lobe cortex (MTLC) and prefrontal cortex. We tested…

Out of One's Mind: A Study of Involuntary Semantic Memories

ERIC Educational Resources Information Center

Kvavilashvili, Lia; Mandler, George

2004-01-01

The study of memories that pop into one's mind without any conscious attempt to retrieve them began only recently. While there are some studies on involuntary autobiographical memories (e.g., Berntsen, 1996, 1998) research on involuntary semantic memories or mind-popping is virtually non-existent. The latter is defined as an involuntary conscious…

Brain mechanisms of persuasion: how 'expert power' modulates memory and attitudes.

PubMed

Klucharev, Vasily; Smidts, Ale; Fernández, Guillén

2008-12-01

Human behaviour is affected by various forms of persuasion. The general persuasive effect of high expertise of the communicator, often referred to as 'expert power', is well documented. We found that a single exposure to a combination of an expert and an object leads to a long-lasting positive effect on memory for and attitude towards the object. Using functional magnetic resonance imaging, we probed the neural processes predicting these behavioural effects. Expert context was associated with distributed left-lateralized brain activity in prefrontal and temporal cortices related to active semantic elaboration. Furthermore, experts enhanced subsequent memory effects in the medial temporal lobe (i.e. in hippocampus and parahippocampal gyrus) involved in memory formation. Experts also affected subsequent attitude effects in the caudate nucleus involved in trustful behaviour, reward processing and learning. These results may suggest that the persuasive effect of experts is mediated by modulation of caudate activity resulting in a re-evaluation of the object in terms of its perceived value. Results extend our view of the functional role of the dorsal striatum in social interaction and enable us to make the first steps toward a neuroscientific model of persuasion.

Brain mechanisms of persuasion: how ‘expert power’ modulates memory and attitudes

PubMed Central

Smidts, Ale; Fernández, Guillén

2008-01-01

Human behaviour is affected by various forms of persuasion. The general persuasive effect of high expertise of the communicator, often referred to as ’expert power’, is well documented. We found that a single exposure to a combination of an expert and an object leads to a long-lasting positive effect on memory for and attitude towards the object. Using functional magnetic resonance imaging, we probed the neural processes predicting these behavioural effects. Expert context was associated with distributed left-lateralized brain activity in prefrontal and temporal cortices related to active semantic elaboration. Furthermore, experts enhanced subsequent memory effects in the medial temporal lobe (i.e. in hippocampus and parahippocampal gyrus) involved in memory formation. Experts also affected subsequent attitude effects in the caudate nucleus involved in trustful behaviour, reward processing and learning. These results may suggest that the persuasive effect of experts is mediated by modulation of caudate activity resulting in a re-evaluation of the object in terms of its perceived value. Results extend our view of the functional role of the dorsal striatum in social interaction and enable us to make the first steps toward a neuroscientific model of persuasion. PMID:19015077

Frequency Monitoring: A Methodology for Assessing the Organization of Information

DTIC Science & Technology

1988-08-01

Memory & Cognition, 6, 410-415. Tulving, E. Episodic and semantic memory (1972). In E. Tulving & W. Donaldson (Ed.), Organization and memory . New...are stored in episodic memory (Tulving, 1972). These global-level memory units enable people to make important decisions about such significant... semantically similar. However, as indicated earlier, an advantage of frequency-estimation tests of memory is that they do not require the presentation of

The role of left prefrontal cortex in language and memory

PubMed Central

Gabrieli, John D. E.; Poldrack, Russell A.; Desmond, John E.

1998-01-01

This article reviews attempts to characterize the mental operations mediated by left inferior prefrontal cortex, especially the anterior and inferior portion of the gyrus, with the functional neuroimaging techniques of positron emission tomography and functional magnetic resonance imaging. Activations in this region occur during semantic, relative to nonsemantic, tasks for the generation of words to semantic cues or the classification of words or pictures into semantic categories. This activation appears in the right prefrontal cortex of people known to be atypically right-hemisphere dominant for language. In this region, activations are associated with meaningful encoding that leads to superior explicit memory for stimuli and deactivations with implicit semantic memory (repetition priming) for words and pictures. New findings are reported showing that patients with global amnesia show deactivations in the same region associated with repetition priming, that activation in this region reflects selection of a response from among numerous relative to few alternatives, and that activations in a portion of this region are associated specifically with semantic relative to phonological processing. It is hypothesized that activations in left inferior prefrontal cortex reflect a domain-specific semantic working memory capacity that is invoked more for semantic than nonsemantic analyses regardless of stimulus modality, more for initial than for repeated semantic analysis of a word or picture, more when a response must be selected from among many than few legitimate alternatives, and that yields superior later explicit memory for experiences. PMID:9448258

From sensorimotor learning to memory cells in prefrontal and temporal association cortex: a neurocomputational study of disembodiment.

PubMed

Pulvermüller, Friedemann; Garagnani, Max

2014-08-01

Memory cells, the ultimate neurobiological substrates of working memory, remain active for several seconds and are most commonly found in prefrontal cortex and higher multisensory areas. However, if correlated activity in "embodied" sensorimotor systems underlies the formation of memory traces, why should memory cells emerge in areas distant from their antecedent activations in sensorimotor areas, thus leading to "disembodiment" (movement away from sensorimotor systems) of memory mechanisms? We modelled the formation of memory circuits in six-area neurocomputational architectures, implementing motor and sensory primary, secondary and higher association areas in frontotemporal cortices along with known between-area neuroanatomical connections. Sensorimotor learning driven by Hebbian neuroplasticity led to formation of cell assemblies distributed across the different areas of the network. These action-perception circuits (APCs) ignited fully when stimulated, thus providing a neural basis for long-term memory (LTM) of sensorimotor information linked by learning. Subsequent to ignition, activity vanished rapidly from APC neurons in sensorimotor areas but persisted in those in multimodal prefrontal and temporal areas. Such persistent activity provides a mechanism for working memory for actions, perceptions and symbols, including short-term phonological and semantic storage. Cell assembly ignition and "disembodied" working memory retreat of activity to multimodal areas are documented in the neurocomputational models' activity dynamics, at the level of single cells, circuits, and cortical areas. Memory disembodiment is explained neuromechanistically by APC formation and structural neuroanatomical features of the model networks, especially the central role of multimodal prefrontal and temporal cortices in bridging between sensory and motor areas. These simulations answer the "where" question of cortical working memory in terms of distributed APCs and their inner structure, which is, in part, determined by neuroanatomical structure. As the neurocomputational model provides a mechanistic explanation of how memory-related "disembodied" neuronal activity emerges in "embodied" APCs, it may be key to solving aspects of the embodiment debate and eventually to a better understanding of cognitive brain functions. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Semantic memory impairment for biological and man-made objects in individuals with amnestic mild cognitive impairment or late-life depression.

PubMed

Callahan, Brandy L; Joubert, Sven; Tremblay, Marie-Pier; Macoir, Joël; Belleville, Sylvie; Rousseau, François; Bouchard, Rémi W; Verret, Louis; Hudon, Carol

2015-06-01

Amnestic mild cognitive impairment (aMCI) and late-life depression (LLD) both increase the risk of developing Alzheimer disease (AD). Very little is known about the similarities and differences between these syndromes. The present study addresses this issue by examining the nature of semantic memory impairment (more precisely, object-based knowledge) in patients at risk of developing AD. Participants were 17 elderly patients with aMCI, 18 patients with aMCI plus depressive symptoms (aMCI/D+), 15 patients with LLD, and 29 healthy controls. All participants were aged 55 years or older and were administered a semantic battery designed to assess semantic knowledge for 16 biological and 16 man-made items. Overall performance of aMCI/D+ participants was significantly worse than the 3 other groups, and performance for questions assessing knowledge for biological items was poorer than for questions relating to man-made items. This study is the first to show that aMCI/D+ is associated with object-based semantic memory impairment. These results support the view that semantic deficits in aMCI are associated with concomitant depressive symptoms. However, depressive symptoms alone do not account exclusively for semantic impairment, since patients with LLD showed no semantic memory deficit. © The Author(s) 2014.

Calcium homeostasis and protein kinase/phosphatase balance participate in nicotine-induced memory improvement in passive avoidance task in mice.

PubMed

Michalak, Agnieszka; Biala, Grazyna

2017-01-15

Long-term potentiation (LTP) and long-term depression (LTD) depend on specific postsynaptic Ca 2+ /calmodulin concentration. LTP results from Ca 2+ influx through the activated NMDA receptors or voltage-gated calcium channels (VGCCs) and is linked with activation of protein kinases including mitogen-activated protein kinase (MAPK). Weaker synaptic stimulation, as a result of low Ca 2+ influx, leads to activation of Ca 2+ /calmodulin-dependent phosphatase (calcineurin - CaN) and triggers LTD. Interestingly, both memory formation and drug addiction share similar neuroplastic changes. Nicotine, which is one of the most common addictive drugs, manifests its memory effects through nicotinic acetylcholine receptors (nAChRs). Because nAChRs may also gate Ca 2+ , it is suggested that calcium signaling pathways are involved in nicotine-induced memory effects. Within the scope of the study was to evaluate the importance of calcium homeostasis and protein kinase/phosphatase balance in nicotine-induced short- and long-term memory effects. To assess memory function in mice passive avoidance test was used. The presented results confirm that acute nicotine (0.1mg/kg) improves short- and long-term memory. Pretreatment with L-type VGCC blockers (amlodipine, nicardipine verapamil) increased nicotine-induced memory improvement in the context of short- and long-term memory. Pretreatment with FK-506 (a potent CaN inhibitor) enhanced short- but not long-term memory effects of nicotine, while SL-327 (a selective MAPK/ERK kinase inhibitor) attenuated both nicotine-induced short- and long-term memory improvement. Acute nicotine enhances both types of memory via L-type VGCC blockade and via ERK1/2 activation. Only short- but not long-term memory enhancement induced by nicotine is dependent on CaN inhibition. Copyright © 2016 Elsevier B.V. All rights reserved.

Cognitive correlates of long-term cannabis use in Costa Rican men.

PubMed

Fletcher, J M; Page, J B; Francis, D J; Copeland, K; Naus, M J; Davis, C M; Morris, R; Krauskopf, D; Satz, P

1996-11-01

Cognitive correlates of long-term cannabis use have been elusive. We tested the hypothesis that long-term cannabis use is associated with deficits in short term memory, working memory, and attention in a literate, westernized culture (Costa Rica) in which the effects of cannabis use can be isolated. Two cohorts of long-term cannabis users and nonusers were studied. Within each cohort, users and nonusers were comparable in age and socioeconomic status. Polydrug users and users who tested positive for the use of cannabis at the time of cognitive assessment after a 72-hour abstention period were excluded. The older cohort (whose age was approximately 45 years) had consumed cannabis for an average of 34 years, and comprised 17 users and 30 nonusers, who had been recruited in San José, Costa Rica, and had been observed since 1973. The younger cohort (whose age was approximately 28 years) had consumed cannabis for an average of 8 years, and comprised 37 users and 49 nonusers. Short-term memory, working memory, and attentional skills were measured in each subject. Older long-term users performed worse than older nonusers on 2 short-term memory tests involving learning lists of words. In addition, older long-term users performed worse than older nonusers on selective and divided attention tasks associated with working memory. No notable differences were apparent between younger users and nonusers. Long-term cannabis use was associated with disruption of short-term memory, working memory, and attentional skills in older long-term cannabis users.

Independence of long-term contextual memory and short-term perceptual hypotheses: Evidence from contextual cueing of interrupted search.

PubMed

Schlagbauer, Bernhard; Mink, Maurice; Müller, Hermann J; Geyer, Thomas

2017-02-01

Observers are able to resume an interrupted search trial faster relative to responding to a new, unseen display. This finding of rapid resumption is attributed to short-term perceptual hypotheses generated on the current look and confirmed upon subsequent looks at the same display. It has been suggested that the contents of perceptual hypotheses are similar to those of other forms of memory acquired long-term through repeated exposure to the same search displays over the course of several trials, that is, the memory supporting "contextual cueing." In three experiments, we investigated the relationship between short-term perceptual hypotheses and long-term contextual memory. The results indicated that long-term, contextual memory of repeated displays neither affected the generation nor the confirmation of short-term perceptual hypotheses for these displays. Furthermore, the analysis of eye movements suggests that long-term memory provides an initial benefit in guiding attention to the target, whereas in subsequent looks guidance is entirely based on short-term perceptual hypotheses. Overall, the results reveal a picture of both long- and short-term memory contributing to reliable performance gains in interrupted search, while exerting their effects in an independent manner.

Epilepsy increases vulnerability of long-term face recognition to proactive interference.

PubMed

Bengner, T; Malina, T; Lindenau, M; Voges, B; Goebell, E; Stodieck, S

2006-02-01

Proactive interference (PI) decreases short- and long-term memory in healthy subjects. Neurological patients exhibit a heightened PI effect on short-term memory. It is, however, not known if PI affects long-term memory in neurological patients. We analyzed whether epilepsy heightens the negative effect of PI on long-term face memory. PI was induced by a list of 20 faces learned 24 hours prior to a target list of 20 faces. We tested immediate and 24-hour recognition for both lists. Twelve healthy controls and 42 patients with generalized epilepsy or temporal lobe epilepsy (TLE) were studied. PI led to a decrease in 24-hour recognition in patients with generalized epilepsy and TLE but not in controls. Thus, PI may cause long-term memory disturbances in epilepsy patients. PI was also associated with decreased short-term memory, but only in right TLE. This confirms the dominant role of the right temporal lobe in short-term face memory.

Protein kinase M ζ and the maintenance of long-term memory.

PubMed

Zhang, Yang; Zong, Wei; Zhang, Lei; Ma, Yuanye; Wang, Jianhong

2016-10-01

Although various molecules have been found to mediate the processes of memory acquisition and consolidation, the molecular mechanism to maintain memory still remains elusive. In recent years, a molecular pathway focusing on protein kinase Mζ (PKMζ) has become of interest to researchers because of its potential role in long-term memory maintenance. PKMζ is an isoform of protein kinase C (PKC) and has a related structure that influences its function in maintaining memory. Considerable evidence has been gathered on PKMζ activity, including loss of function studies using PKMζ inhibitors, such as PKMζ inhibitory peptide (ZIP), suggesting PKMζ plays an important role in long-term memory maintenance. This review provides an overview of the role of PKMζ in long-term memory and outlines the molecular structure of PKMζ, the molecular mechanism of PKMζ in long-term memory maintenance and future directions of PKMζ research. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mnemonic function in small vessel disease and associations with white matter tract microstructure.

PubMed

Metoki, Athanasia; Brookes, Rebecca L; Zeestraten, Eva; Lawrence, Andrew J; Morris, Robin G; Barrick, Thomas R; Markus, Hugh S; Charlton, Rebecca A

2017-09-01

Cerebral small vessel disease (SVD) is associated with deficits in working memory, with a relative sparing of long-term memory; function may be influenced by white matter microstructure. Working and long-term memory were examined in 106 patients with SVD and 35 healthy controls. Microstructure was measured in the uncinate fasciculi and cingula. Working memory was more impaired than long-term memory in SVD, but both abilities were reduced compared to controls. Regression analyses found that having SVD explained the variance in memory functions, with additional variance explained by the cingula (working memory) and uncinate (long-term memory). Performance can be explained in terms of integrity loss in specific white matter tract associated with mnemonic functions. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Hippocampal activation during episodic and semantic memory retrieval: comparing category production and category cued recall.

PubMed

Ryan, Lee; Cox, Christine; Hayes, Scott M; Nadel, Lynn

2008-01-01

Whether or not the hippocampus participates in semantic memory retrieval has been the focus of much debate in the literature. However, few neuroimaging studies have directly compared hippocampal activation during semantic and episodic retrieval tasks that are well matched in all respects other than the source of the retrieved information. In Experiment 1, we compared hippocampal fMRI activation during a classic semantic memory task, category production, and an episodic version of the same task, category cued recall. Left hippocampal activation was observed in both episodic and semantic conditions, although other regions of the brain clearly distinguished the two tasks. Interestingly, participants reported using retrieval strategies during the semantic retrieval task that relied on autobiographical and spatial information; for example, visualizing themselves in their kitchen while producing items for the category kitchen utensils. In Experiment 2, we considered whether the use of these spatial and autobiographical retrieval strategies could have accounted for the hippocampal activation observed in Experiment 1. Categories were presented that elicited one of three retrieval strategy types, autobiographical and spatial, autobiographical and nonspatial, and neither autobiographical nor spatial. Once again, similar hippocampal activation was observed for all three category types, regardless of the inclusion of spatial or autobiographical content. We conclude that the distinction between semantic and episodic memory is more complex than classic memory models suggest.

Hippocampal Activation during Episodic and Semantic Memory Retrieval: Comparing Category Production and Category Cued Recall

PubMed Central

Ryan, Lee; Cox, Christine; Hayes, Scott M.; Nadel, Lynn

2008-01-01

Whether or not the hippocampus participates in semantic memory retrieval has been the focus of much debate in the literature. However, few neuroimaging studies have directly compared hippocampal activation during semantic and episodic retrieval tasks that are well matched in all respects other than the source of the retrieved information. In Experiment 1, we compared hippocampal fMRI activation during a classic semantic memory task, category production, and an episodic version of the same task, category cued recall. Left hippocampal activation was observed in both episodic and semantic conditions, although other regions of the brain clearly distinguished the two tasks. Interestingly, participants reported using retrieval strategies during the semantic retrieval task that relied on autobiographical and spatial information; for example, visualizing themselves in their kitchen while producing items for the category kitchen utensils. In Experiment 2, we considered whether the use of these spatial and autobiographical retrieval strategies could have accounted for the hippocampal activation observed in Experiment 1. Categories were presented that elicited one of three retrieval strategy types, autobiographical and spatial, autobiographical and nonspatial, and neither autobiographical nor spatial. Once again, similar hippocampal activation was observed for all three category types, regardless of the inclusion of spatial or autobiographical content. We conclude that the distinction between semantic and episodic memory is more complex than classic memory models suggest. PMID:18420234

The roles of Eph receptors in contextual fear conditioning memory formation.

PubMed

Dines, Monica; Grinberg, Svetlana; Vassiliev, Maria; Ram, Alon; Tamir, Tal; Lamprecht, Raphael

2015-10-01

Eph receptors regulate glutamate receptors functions, neuronal morphology and synaptic plasticity, cellular events believed to be involved in memory formation. In this study we aim to explore the roles of Eph receptors in learning and memory. Toward that end, we examined the roles of EphB2 and EphA4 receptors, key regulators of synaptic functions, in fear conditioning memory formation. We show that mice lacking EphB2 (EphB2(-/-)) are impaired in short- and long-term contextual fear conditioning memory. Mice that express a carboxy-terminally truncated form of EphB2 that lacks forward signaling, instead of the full EphB2, are impaired in long-term, but not short-term, contextual fear conditioning memory. Long-term contextual fear conditioning memory is attenuated in CaMKII-cre;EphA4(lx/-) mice where EphA4 is removed from all pyramidal neurons of the forebrain. Mutant mice with targeted kinase-dead EphA4 (EphA4(KD)) exhibit intact long-term contextual fear conditioning memory showing that EphA4 kinase-mediated forward signaling is not needed for contextual fear memory formation. The ability to form long-term conditioned taste aversion (CTA) memory is not impaired in the EphB2(-/-) and CaMKII-cre;EphA4(lx/-) mice. We conclude that EphB2 forward signaling is required for long-term contextual fear conditioning memory formation. In contrast, EphB2 mediates short-term contextual fear conditioning memory formation in a forward signaling-independent manner. EphA4 mediates long-term contextual fear conditioning memory formation in a kinase-independent manner. Copyright © 2015 Elsevier Inc. All rights reserved.

Brief, pre-learning stress reduces false memory production and enhances true memory selectively in females.

PubMed

Zoladz, Phillip R; Peters, David M; Kalchik, Andrea E; Hoffman, Mackenzie M; Aufdenkampe, Rachael L; Woelke, Sarah A; Wolters, Nicholas E; Talbot, Jeffery N

2014-04-10

Some of the previous research on stress-memory interactions has suggested that stress increases the production of false memories. However, as accumulating work has shown that the effects of stress on learning and memory depend critically on the timing of the stressor, we hypothesized that brief stress administered immediately before learning would reduce, rather than increase, false memory production. In the present study, participants submerged their dominant hand in a bath of ice cold water (stress) or sat quietly (no stress) for 3 min. Then, participants completed a short-term memory task, the Deese-Roediger-McDermott paradigm, in which they were presented with 10 different lists of semantically related words (e.g., candy, sour, sugar) and, after each list, were tested for their memory of presented words (e.g., candy), non-presented unrelated "distractor" words (e.g., hat), and non-presented semantically related "critical lure" words (e.g., sweet). Stress, overall, significantly reduced the number of critical lures recalled (i.e., false memory) by participants. In addition, stress enhanced memory for the presented words (i.e., true memory) in female, but not male, participants. These findings reveal that stress does not unequivocally enhance false memory production and that the timing of the stressor is an important variable that could mediate such effects. Such results could have important implications for understanding the dependability of eyewitness accounts of events that are observed following stress. Copyright © 2014 Elsevier Inc. All rights reserved.

Episodic but not semantic order memory difficulties in autism spectrum disorder: evidence from the Historical Figures Task.

PubMed

Gaigg, Sebastian B; Bowler, Dermot M; Gardiner, John M

2014-01-01

Considerable evidence suggests that the episodic memory system operates abnormally in autism spectrum disorder (ASD) whereas the functions of the semantic memory system are relatively preserved. Here we show that the same dissociation also applies to the domain of order memory. We asked adult participants to order the names of famous historical figures either according to their chronological order in history (probing semantic memory) or according to a random sequence shown once on a screen (probing episodic memory). As predicted, adults with ASD performed less well than age- and IQ-matched comparison individuals only on the episodic task. This observation is of considerable importance in the context of developmental theory because semantic and episodic order memory abilities can be dissociated in typically developing infants before they reach the age at which the behavioural markers associated with ASD are first apparent. This raises the possibility that early emerging memory abnormalities play a role in shaping the developmental trajectory of the disorder. We discuss the broader implications of this possibility and highlight the urgent need for greater scrutiny of memory competences in ASD early in development.

The effects of marital status on episodic and semantic memory in healthy middle-aged and old individuals.

PubMed

Mousavi-Nasab, S-M-Hossein; Kormi-Nouri, Reza; Sundström, Anna; Nilsson, Lars-Göran

2012-02-01

The present study examined the influences of marital status on different episodic and semantic memory tasks. A total of 1882 adult men and women participated in a longitudinal project (Betula) on memory, health and aging. The participants were grouped into two age cohorts, 35-60 and 65-85, and studied over a period of 5 years. Episodic memory tasks concerned recognition and recall, whereas semantic memory tasks concerned knowledge and fluency. The results showed, after controlling for education, some diseases, chronological age and leisure activity as covariates, that there were significant differences between married and single individuals in episodic memory, but not in semantic memory. Married people showed significantly better memory performances than singles in both subsystems of episodic memory, that is, recall and recognition. Also, the rate of decline in episodic memory was significantly larger for singles and widowed than other groups over the 5-year time period in both age groups. The findings demonstrate that the positive relation found between marriage and health can be extended to the relation between marriage and cognitive performance. This effect might be explained by the role played by cognitive stimulation in memory and cognition. © 2011 The Authors. Scandinavian Journal of Psychology © 2011 The Scandinavian Psychological Associations.

The facilitative effects of glucose ingestion on memory retrieval in younger and older adults: is task difficulty or task domain critical?

PubMed

Riby, Leigh M; McMurtrie, Hazel; Smallwood, Jonathan; Ballantyne, Carrie; Meikle, Andrew; Smith, Emily

2006-02-01

The ingestion of a glucose-containing drink has been shown to improve cognitive performance, particularly memory functioning. However, it remains unclear as to the extent to which task domain and task difficulty moderate the glucose enhancement effect. The aim of this research was to determine whether boosts in performance are restricted to particular classes of memory (episodic v. semantic) or to tasks of considerable cognitive load. A repeated measures (25 g glucose v. saccharin), counterbalanced, double-blind design was used with younger and older adults. Participants performed a battery of episodic (e.g. paired associate learning) and semantic memory (e.g. category verification) tasks under low and high cognitive load. Electrophysiological measures (heart rate and galvanic skin response) of arousal and mental effort were also gathered. The results indicated that whilst glucose appeared to aid episodic remembering, cognitive load did not exaggerate the facilitative effect. For semantic memory, there was little evidence to suggest that glucose can boost semantic memory retrieval even when the load was manipulated. One exception was that glucose facilitated performance during the difficult category fluency task. Regardless, the present findings are consistent with the domain-specific account in which glucose acts primarily on the hippocampal region, which is known to support episodic memory. The possible contribution of the hippocampus in semantic memory processing is also discussed.

The Longevity of Hippocampus-Dependent Memory Is Orchestrated by the Locus Coeruleus-Noradrenergic System

PubMed Central

2017-01-01

The locus coeruleus is connected to the dorsal hippocampus via strong fiber projections. It becomes activated after arousal and novelty, whereupon noradrenaline is released in the hippocampus. Noradrenaline from the locus coeruleus is involved in modulating the encoding, consolidation, retrieval, and reversal of hippocampus-based memory. Memory storage can be modified by the activation of the locus coeruleus and subsequent facilitation of hippocampal long-term plasticity in the forms of long-term depression and long-term potentiation. Recent evidence indicates that noradrenaline and dopamine are coreleased in the hippocampus from locus coeruleus terminals, thus fostering neuromodulation of long-term synaptic plasticity and memory. Noradrenaline is an inductor of epigenetic modifications regulating transcriptional control of synaptic long-term plasticity to gate the endurance of memory storage. In conclusion, locus coeruleus activation primes the persistence of hippocampus-based long-term memory. PMID:28695015

The Semantic Web and Educational Technology

ERIC Educational Resources Information Center

Maddux, Cleborne D., Ed.

2008-01-01

The "Semantic Web" is an idea proposed by Tim Berners-Lee, the inventor of the "World Wide Web." The topic has been generating a great deal of interest and enthusiasm, and there is a rapidly growing body of literature dealing with it. This article attempts to explain how the Semantic Web would work, and explores short-term and long-term…

Emotionally Negative Pictures Enhance Gist Memory

PubMed Central

Bookbinder, S. H.; Brainerd, C. J.

2016-01-01

In prior work on how true and false memory are influenced by emotion, valence and arousal have often been conflated. Thus, it is difficult to say which specific effects are due to valence and which are due to arousal. In the present research, we used a picture-memory paradigm that allowed emotional valence to be manipulated with arousal held constant. Negatively-valenced pictures elevated both true and false memory, relative to positive and neutral pictures. Conjoint recognition modeling revealed that negative valence (a) reduced erroneous suppression of true memories and (b) increased the familiarity of the semantic content of both true and false memories. Overall, negative valence impaired the verbatim side of episodic memory but enhanced the gist side, and these effects persisted even after a week-long delay. PMID:27454002

Different Ways to Cue a Coherent Memory System: A Theory for Episodic, Semantic, and Procedural Tasks.

ERIC Educational Resources Information Center

Humphreys, Michael S.; And Others

1989-01-01

An associative theory of memory is proposed to serve as a counterexample to claims that dissociations among episodic, semantic, and procedural memory tasks necessitate separate memory systems. The theory is based on task analyses of matching (recognition and familiarity judgments), retrieval (cued recall), and production (free association). (TJH)

Congenital blindness improves semantic and episodic memory.

PubMed

Pasqualotto, Achille; Lam, Jade S Y; Proulx, Michael J

2013-05-01

Previous studies reported that congenitally blind people possess superior verb-generation skills. Here we tested the impact of blindness on capacity and the fidelity of semantic memory by using a false memory paradigm. In the Deese-Roediger-McDermott paradigm, participants study lists of words that are all semantically related to a lure that is not presented. Subsequently, participants frequently recall the missing lure. We found that congenitally blind participants have enhanced memory performance for recalling the presented words and reduced false memories for the lure. The dissociation of memory capacity and fidelity provides further evidence for enhanced verbal ability in the blind, supported by their broader structural and functional brain reorganisation. Copyright © 2013 Elsevier B.V. All rights reserved.

Resolving semantic and proactive interference in memory over the short-term.

PubMed

Atkins, Alexandra S; Berman, Marc G; Reuter-Lorenz, Patricia A; Lewis, Richard L; Jonides, John

2011-07-01

Interference is a major source of short-term errors of memory. The present investigation explores the relationship between two important forms of interference: proactive interference (PI), induced by the need to reject recently studied items no longer relevant to task performance, and semantic interference (SI), induced by the need to reject lures sharing a meaningful relationship with current memoranda. We explore the possibility that shared cognitive control processes are recruited to resolve both forms of interference. In Experiment 1, we find that the requirement to engage in articulatory suppression during the retention interval of tasks that induce either PI or SI increases both forms of interference similarly and selectively. In Experiment 2, we develop a task to examine PI and SI within the same experimental context. The results show interactive effects between factors that lead to the two forms of interference. Taken together, these findings support contextual-cuing models of short-term remembering (Nairne, Annual Review of Psychology, 53, 53-81 2002), where the context in which retrieval occurs can influence susceptibility to interference. Lastly, we discuss several theoretical hypotheses concerning the cognitive control processes that are recruited to resolve SI and PI in short-term remembering.

Resolving semantic and proactive interference in memory over the short-term

PubMed Central

Reuter-Lorenz, Patricia A.; Lewis, Richard L.; Jonides, John

2011-01-01

Interference is a major source of short-term errors of memory. The present investigation explores the relationship between two important forms of interference: proactive interference (PI), induced by the need to reject recently studied items no longer relevant to task performance, and semantic interference (SI), induced by the need to reject lures sharing a meaningful relationship with current memoranda. We explore the possibility that shared cognitive control processes are recruited to resolve both forms of interference. In Experiment 1, we find that the requirement to engage in articulatory suppression during the retention interval of tasks that induce either PI or SI increases both forms of interference similarly and selectively. In Experiment 2, we develop a task to examine PI and SI within the same experimental context. The results show interactive effects between factors that lead to the two forms of interference. Taken together, these findings support contextual-cuing models of short-term remembering (Nairne, Annual Review of Psychology, 53, 53–81 2002), where the context in which retrieval occurs can influence susceptibility to interference. Lastly, we discuss several theoretical hypotheses concerning the cognitive control processes that are recruited to resolve SI and PI in short-term remembering. PMID:21327614

Early remodeling of the neocortex upon episodic memory encoding

PubMed Central

Bero, Adam W.; Meng, Jia; Cho, Sukhee; Shen, Abra H.; Canter, Rebecca G.; Ericsson, Maria; Tsai, Li-Huei

2014-01-01

Understanding the mechanisms by which long-term memories are formed and stored in the brain represents a central aim of neuroscience. Prevailing theory suggests that long-term memory encoding involves early plasticity within hippocampal circuits, whereas reorganization of the neocortex is thought to occur weeks to months later to subserve remote memory storage. Here we report that long-term memory encoding can elicit early transcriptional, structural, and functional remodeling of the neocortex. Parallel studies using genome-wide RNA sequencing, ultrastructural imaging, and whole-cell recording in wild-type mice suggest that contextual fear conditioning initiates a transcriptional program in the medial prefrontal cortex (mPFC) that is accompanied by rapid expansion of the synaptic active zone and postsynaptic density, enhanced dendritic spine plasticity, and increased synaptic efficacy. To address the real-time contribution of the mPFC to long-term memory encoding, we performed temporally precise optogenetic inhibition of excitatory mPFC neurons during contextual fear conditioning. Using this approach, we found that real-time inhibition of the mPFC inhibited activation of the entorhinal–hippocampal circuit and impaired the formation of long-term associative memory. These findings suggest that encoding of long-term episodic memory is associated with early remodeling of neocortical circuits, identify the prefrontal cortex as a critical regulator of encoding-induced hippocampal activation and long-term memory formation, and have important implications for understanding memory processing in healthy and diseased brain states. PMID:25071187

Individual differences in white matter microstructure predict semantic control.

PubMed

Nugiel, Tehila; Alm, Kylie H; Olson, Ingrid R

2016-12-01

In everyday conversation, we make many rapid choices between competing concepts and words in order to convey our intent. This process is termed semantic control, and it is thought to rely on information transmission between a distributed semantic store in the temporal lobes and a more discrete region, optimized for retrieval and selection, in the left inferior frontal gyrus. Here, we used diffusion tensor imaging in a group of neurologically normal young adults to investigate the relationship between semantic control and white matter tracts that have been implicated in semantic memory retrieval. Participants completed a verb generation task that taps semantic control (Snyder & Munakata, 2008; Snyder et al., 2010) and underwent a diffusion imaging scan. Deterministic tractography was performed to compute indices representing the microstructural properties of the inferior fronto-occipital fasciculus (IFOF), the uncinate fasciculus (UF), and the inferior longitudinal fasciculus (ILF). Microstructural measures of the UF failed to predict semantic control performance. However, there was a significant relationship between microstructure of the left IFOF and ILF and individual differences in semantic control. Our findings support the view put forth by Duffau (2013) that the IFOF is a key structural pathway in semantic retrieval.

Utilizing the Structure and Content Information for XML Document Clustering

NASA Astrophysics Data System (ADS)

Tran, Tien; Kutty, Sangeetha; Nayak, Richi

This paper reports on the experiments and results of a clustering approach used in the INEX 2008 document mining challenge. The clustering approach utilizes both the structure and content information of the Wikipedia XML document collection. A latent semantic kernel (LSK) is used to measure the semantic similarity between XML documents based on their content features. The construction of a latent semantic kernel involves the computing of singular vector decomposition (SVD). On a large feature space matrix, the computation of SVD is very expensive in terms of time and memory requirements. Thus in this clustering approach, the dimension of the document space of a term-document matrix is reduced before performing SVD. The document space reduction is based on the common structural information of the Wikipedia XML document collection. The proposed clustering approach has shown to be effective on the Wikipedia collection in the INEX 2008 document mining challenge.

Semantic Knowledge for Famous Names in Mild Cognitive Impairment

PubMed Central

Seidenberg, Michael; Guidotti, Leslie; Nielson, Kristy A.; Woodard, John L.; Durgerian, Sally; Zhang, Qi; Gander, Amelia; Antuono, Piero; Rao, Stephen M.

2008-01-01

Person identification represents a unique category of semantic knowledge that is commonly impaired in Alzheimer's Disease (AD), but has received relatively little investigation in patients with Mild Cognitive Impairment (MCI). The current study examined the retrieval of semantic knowledge for famous names from three time epochs (recent, remote, and enduring) in two participant groups; 23 aMCI patients and 23 healthy elderly controls. The aMCI group was less accurate and produced less semantic knowledge than controls for famous names. Names from the enduring period were recognized faster than both recent and remote names in both groups, and remote names were recognized more quickly than recent names. Episodic memory performance was correlated with greater semantic knowledge particularly for recent names. We suggest that the anterograde memory deficits in the aMCI group interferes with learning of recent famous names and as a result produces difficulties with updating and integrating new semantic information with previously stored information. The implications of these findings for characterizing semantic memory deficits in MCI are discussed. PMID:19128524

The Semantic Distance Task: Quantifying Semantic Distance with Semantic Network Path Length

ERIC Educational Resources Information Center

Kenett, Yoed N.; Levi, Effi; Anaki, David; Faust, Miriam

2017-01-01

Semantic distance is a determining factor in cognitive processes, such as semantic priming, operating upon semantic memory. The main computational approach to compute semantic distance is through latent semantic analysis (LSA). However, objections have been raised against this approach, mainly in its failure at predicting semantic priming. We…

The structure of semantic person memory: evidence from semantic priming in person recognition.

PubMed

Wiese, Holger

2011-11-01

This paper reviews research on the structure of semantic person memory as examined with semantic priming. In this experimental paradigm, a familiarity decision on a target face or written name is usually faster when it is preceded by a related as compared to an unrelated prime. This effect has been shown to be relatively short lived and susceptible to interfering items. Moreover, semantic priming can cross stimulus domains, such that a written name can prime a target face and vice versa. However, it remains controversial whether representations of people are stored in associative networks based on co-occurrence, or in more abstract semantic categories. In line with prominent cognitive models of face recognition, which explain semantic priming by shared semantic information between prime and target, recent research demonstrated that priming could be obtained from purely categorically related, non-associated prime/target pairs. Although strategic processes, such as expectancy and retrospective matching likely contribute, there is also evidence for a non-strategic contribution to priming, presumably related to spreading activation. Finally, a semantic priming effect has been demonstrated in the N400 event-related potential (ERP) component, which may reflect facilitated access to semantic information. It is concluded that categorical relatedness is one organizing principle of semantic person memory. ©2011 The British Psychological Society.

Compensation for PKMζ in long-term potentiation and spatial long-term memory in mutant mice.

PubMed

Tsokas, Panayiotis; Hsieh, Changchi; Yao, Yudong; Lesburguères, Edith; Wallace, Emma Jane Claire; Tcherepanov, Andrew; Jothianandan, Desingarao; Hartley, Benjamin Rush; Pan, Ling; Rivard, Bruno; Farese, Robert V; Sajan, Mini P; Bergold, Peter John; Hernández, Alejandro Iván; Cottrell, James E; Shouval, Harel Z; Fenton, André Antonio; Sacktor, Todd Charlton

2016-05-17

PKMζ is a persistently active PKC isoform proposed to maintain late-LTP and long-term memory. But late-LTP and memory are maintained without PKMζ in PKMζ-null mice. Two hypotheses can account for these findings. First, PKMζ is unimportant for LTP or memory. Second, PKMζ is essential for late-LTP and long-term memory in wild-type mice, and PKMζ-null mice recruit compensatory mechanisms. We find that whereas PKMζ persistently increases in LTP maintenance in wild-type mice, PKCι/λ, a gene-product closely related to PKMζ, persistently increases in LTP maintenance in PKMζ-null mice. Using a pharmacogenetic approach, we find PKMζ-antisense in hippocampus blocks late-LTP and spatial long-term memory in wild-type mice, but not in PKMζ-null mice without the target mRNA. Conversely, a PKCι/λ-antagonist disrupts late-LTP and spatial memory in PKMζ-null mice but not in wild-type mice. Thus, whereas PKMζ is essential for wild-type LTP and long-term memory, persistent PKCι/λ activation compensates for PKMζ loss in PKMζ-null mice.

Musicians have better memory than nonmusicians: A meta-analysis.

PubMed

Talamini, Francesca; Altoè, Gianmarco; Carretti, Barbara; Grassi, Massimo

2017-01-01

Several studies have found that musicians perform better than nonmusicians in memory tasks, but this is not always the case, and the strength of this apparent advantage is unknown. Here, we conducted a meta-analysis with the aim of clarifying whether musicians perform better than nonmusicians in memory tasks. Education Source; PEP (WEB)-Psychoanalytic Electronic Publishing; Psychology and Behavioral Science (EBSCO); PsycINFO (Ovid); PubMed; ScienceDirect-AllBooks Content (Elsevier API); SCOPUS (Elsevier API); SocINDEX with Full Text (EBSCO) and Google Scholar were searched for eligible studies. The selected studies involved two groups of participants: young adult musicians and nonmusicians. All the studies included memory tasks (loading long-term, short-term or working memory) that contained tonal, verbal or visuospatial stimuli. Three meta-analyses were run separately for long-term memory, short-term memory and working memory. We collected 29 studies, including 53 memory tasks. The results showed that musicians performed better than nonmusicians in terms of long-term memory, g = .29, 95% CI (.08-.51), short-term memory, g = .57, 95% CI (.41-.73), and working memory, g = .56, 95% CI (.33-.80). To further explore the data, we included a moderator (the type of stimulus presented, i.e., tonal, verbal or visuospatial), which was found to influence the effect size for short-term and working memory, but not for long-term memory. In terms of short-term and working memory, the musicians' advantage was large with tonal stimuli, moderate with verbal stimuli, and small or null with visuospatial stimuli. The three meta-analyses revealed a small effect size for long-term memory, and a medium effect size for short-term and working memory, suggesting that musicians perform better than nonmusicians in memory tasks. Moreover, the effect of the moderator suggested that, the type of stimuli influences this advantage.

Musicians have better memory than nonmusicians: A meta-analysis

PubMed Central

Altoè, Gianmarco; Carretti, Barbara; Grassi, Massimo

2017-01-01

Background Several studies have found that musicians perform better than nonmusicians in memory tasks, but this is not always the case, and the strength of this apparent advantage is unknown. Here, we conducted a meta-analysis with the aim of clarifying whether musicians perform better than nonmusicians in memory tasks. Methods Education Source; PEP (WEB)—Psychoanalytic Electronic Publishing; Psychology and Behavioral Science (EBSCO); PsycINFO (Ovid); PubMed; ScienceDirect—AllBooks Content (Elsevier API); SCOPUS (Elsevier API); SocINDEX with Full Text (EBSCO) and Google Scholar were searched for eligible studies. The selected studies involved two groups of participants: young adult musicians and nonmusicians. All the studies included memory tasks (loading long-term, short-term or working memory) that contained tonal, verbal or visuospatial stimuli. Three meta-analyses were run separately for long-term memory, short-term memory and working memory. Results We collected 29 studies, including 53 memory tasks. The results showed that musicians performed better than nonmusicians in terms of long-term memory, g = .29, 95% CI (.08–.51), short-term memory, g = .57, 95% CI (.41–.73), and working memory, g = .56, 95% CI (.33–.80). To further explore the data, we included a moderator (the type of stimulus presented, i.e., tonal, verbal or visuospatial), which was found to influence the effect size for short-term and working memory, but not for long-term memory. In terms of short-term and working memory, the musicians’ advantage was large with tonal stimuli, moderate with verbal stimuli, and small or null with visuospatial stimuli. Conclusions The three meta-analyses revealed a small effect size for long-term memory, and a medium effect size for short-term and working memory, suggesting that musicians perform better than nonmusicians in memory tasks. Moreover, the effect of the moderator suggested that, the type of stimuli influences this advantage. PMID:29049416

Anterograde and retrograde amnesia in a person with bilateral fornix lesions following removal of a colloid cyst.

PubMed

Poreh, Amir; Winocur, Gordon; Moscovitch, Morris; Backon, Matti; Goshen, Elinor; Ram, Zvi; Feldman, Zeev

2006-01-01

AD, a 45-year-old man, presented with a severe and global anterograde amnesia following surgery for removal of a colloid cyst. Structural neuroimaging confirmed bilateral lesions to the fornix and a small lesion in the basal forebrain. Testing for remote episodic memory of autobiographical events, and for remote semantic memory of personal and public events, and of famous people, revealed that AD had a severe retrograde amnesia for autobiographical episodes that covered his entire lifetime, and a time-limited retrograde amnesia for semantic memory. Because the fornix and basal forebrain lesions disrupted major afferent and efferent pathways of the hippocampus, it was concluded that the integrity of the hippocampus and its projections are needed to retain and/or recover autobiographical memories no matter how old they are. By contrast, hippocampal contribution to semantic memory is time-limited. These findings were interpreted as consistent with Multiple Trace Theory, which holds that the hippocampal system is essential for recovering contextually rich memories no matter how old they are, but is not needed for recovering semantic memories.

BDNF Variants May Modulate Long-Term Visual Memory Performance in a Healthy Cohort

PubMed Central

Avgan, Nesli; Sutherland, Heidi G.; Spriggens, Lauren K.; Yu, Chieh; Ibrahim, Omar; Bellis, Claire; Haupt, Larisa M.; Shum, David H. K.; Griffiths, Lyn R.

2017-01-01

Brain-derived neurotrophic factor (BDNF) is involved in numerous cognitive functions including learning and memory. BDNF plays an important role in synaptic plasticity in humans and rats with BDNF shown to be essential for the formation of long-term memories. We previously identified a significant association between the BDNF Val66Met polymorphism (rs6265) and long-term visual memory (p-value = 0.003) in a small cohort (n = 181) comprised of healthy individuals who had been phenotyped for various aspects of memory function. In this study, we have extended the cohort to 597 individuals and examined multiple genetic variants across both the BDNF and BDNF-AS genes for association with visual memory performance as assessed by the Wechsler Memory Scale—Fourth Edition subtests Visual Reproduction I and II (VR I and II). VR I assesses immediate visual memory, whereas VR II assesses long-term visual memory. Genetic association analyses were performed for 34 single nucleotide polymorphisms genotyped on Illumina OmniExpress BeadChip arrays with the immediate and long-term visual memory phenotypes. While none of the BDNF and BDNF-AS variants were shown to be significant for immediate visual memory, we found 10 variants (including the Val66Met polymorphism (p-value = 0.006)) that were nominally associated, and three variants (two variants in BDNF and one variant in the BDNF-AS locus) that were significantly associated with long-term visual memory. Our data therefore suggests a potential role for BDNF, and its anti-sense transcript BDNF-AS, in long-term visual memory performance. PMID:28304362

BDNF Variants May Modulate Long-Term Visual Memory Performance in a Healthy Cohort.

PubMed

Avgan, Nesli; Sutherland, Heidi G; Spriggens, Lauren K; Yu, Chieh; Ibrahim, Omar; Bellis, Claire; Haupt, Larisa M; Shum, David H K; Griffiths, Lyn R

2017-03-17

Brain-derived neurotrophic factor (BDNF) is involved in numerous cognitive functions including learning and memory. BDNF plays an important role in synaptic plasticity in humans and rats with BDNF shown to be essential for the formation of long-term memories. We previously identified a significant association between the BDNF Val66Met polymorphism (rs6265) and long-term visual memory ( p -value = 0.003) in a small cohort ( n = 181) comprised of healthy individuals who had been phenotyped for various aspects of memory function. In this study, we have extended the cohort to 597 individuals and examined multiple genetic variants across both the BDNF and BDNF-AS genes for association with visual memory performance as assessed by the Wechsler Memory Scale-Fourth Edition subtests Visual Reproduction I and II (VR I and II). VR I assesses immediate visual memory, whereas VR II assesses long-term visual memory. Genetic association analyses were performed for 34 single nucleotide polymorphisms genotyped on Illumina OmniExpress BeadChip arrays with the immediate and long-term visual memory phenotypes. While none of the BDNF and BDNF-AS variants were shown to be significant for immediate visual memory, we found 10 variants (including the Val66Met polymorphism ( p -value = 0.006)) that were nominally associated, and three variants (two variants in BDNF and one variant in the BDNF-AS locus) that were significantly associated with long-term visual memory. Our data therefore suggests a potential role for BDNF , and its anti-sense transcript BDNF-AS , in long-term visual memory performance.

The semantic distance task: Quantifying semantic distance with semantic network path length.

PubMed

Kenett, Yoed N; Levi, Effi; Anaki, David; Faust, Miriam

2017-09-01

Semantic distance is a determining factor in cognitive processes, such as semantic priming, operating upon semantic memory. The main computational approach to compute semantic distance is through latent semantic analysis (LSA). However, objections have been raised against this approach, mainly in its failure at predicting semantic priming. We propose a novel approach to computing semantic distance, based on network science methodology. Path length in a semantic network represents the amount of steps needed to traverse from 1 word in the network to the other. We examine whether path length can be used as a measure of semantic distance, by investigating how path length affect performance in a semantic relatedness judgment task and recall from memory. Our results show a differential effect on performance: Up to 4 steps separating between word-pairs, participants exhibit an increase in reaction time (RT) and decrease in the percentage of word-pairs judged as related. From 4 steps onward, participants exhibit a significant decrease in RT and the word-pairs are dominantly judged as unrelated. Furthermore, we show that as path length between word-pairs increases, success in free- and cued-recall decreases. Finally, we demonstrate how our measure outperforms computational methods measuring semantic distance (LSA and positive pointwise mutual information) in predicting participants RT and subjective judgments of semantic strength. Thus, we provide a computational alternative to computing semantic distance. Furthermore, this approach addresses key issues in cognitive theory, namely the breadth of the spreading activation process and the effect of semantic distance on memory retrieval. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Mechanisms of Translation Control Underlying Long-lasting Synaptic Plasticity and the Consolidation of Long-term Memory

PubMed Central

Santini, Emanuela; Huynh, Thu N.; Klann, Eric

2018-01-01

The complexity of memory formation and its persistence is a phenomenon that has been studied intensely for centuries. Memory exists in many forms and is stored in various brain regions. Generally speaking, memories are reorganized into broadly distributed cortical networks over time through systems level consolidation. At the cellular level, storage of information is believed to initially occur via altered synaptic strength by processes such as long-term potentiation (LTP). New protein synthesis is required for long-lasting synaptic plasticity as well as for the formation of long-term memory. The mammalian target of rapamycin complex 1 (mTORC1) is a critical regulator of cap-dependent protein synthesis and is required for numerous forms of long-lasting synaptic plasticity and long-term memory. As such, the study of mTORC1 and protein factors that control translation initiation and elongation have enhanced our understanding of how the process of protein synthesis is regulated during memory formation. Herein we will discuss the molecular mechanisms that regulate protein synthesis as well as pharmacological and genetic manipulations that demonstrate the requirement for proper translational control in long-lasting synaptic plasticity and long-term memory formation. PMID:24484700

The interaction of short-term and long-term memory in phonetic category formation

NASA Astrophysics Data System (ADS)

Harnsberger, James D.

2002-05-01

This study examined the role that short-term memory capacity plays in the relationship between novel stimuli (e.g., non-native speech sounds, native nonsense words) and phonetic categories in long-term memory. Thirty native speakers of American English were administered five tests: categorial AXB discrimination using nasal consonants from Malayalam; categorial identification, also using Malayalam nasals, which measured the influence of phonetic categories in long-term memory; digit span; nonword span, a short-term memory measure mediated by phonetic categories in long-term memory; and paired-associate word learning (word-word and word-nonword pairs). The results showed that almost all measures were significantly correlated with one another. The strongest predictor for the discrimination and word-nonword learning results was nonword (r=+0.62) and digit span (r=+0.51), respectively. When the identification test results were partialed out, only nonword span significantly correlated with discrimination. The results show a strong influence of short-term memory capacity on the encoding of phonetic detail within phonetic categories and suggest that long-term memory representations regulate the capacity of short-term memory to preserve information for subsequent encoding. The results of this study will also be discussed with regards to resolving the tension between episodic and abstract models of phonetic category structure.

The Role of Long-Term Memory in a Test of Visual Working Memory: Proactive Facilitation but No Proactive Interference

ERIC Educational Resources Information Center

Oberauer, Klaus; Awh, Edward; Sutterer, David W.

2017-01-01

We report 4 experiments examining whether associations in visual working memory are subject to proactive interference from long-term memory (LTM). Following a long-term learning phase in which participants learned the colors of 120 unique objects, a working memory (WM) test was administered in which participants recalled the precise colors of 3…